## Jahresübersicht für das Jahr 2021

07 Jan 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14 Uhr c.t., None
 Prof. Dr. Antoine Browaeys, Laboratoire Charles Fabry, Palaiseau, France This talk will present our effort to control and use the dipole-dipole interactions between cold atoms in order to implement spin Hamiltonians useful for quantum simulation of condensed matter or quantum optics situations. We trap individual atoms in arrays of optical tweezers separated by a few micrometers. We create almost arbitrary geometries of the atomic arrays in two and three dimensions up to about 200 atoms. To make the atoms interact, we either excite them to Rydberg states or induce optical dipoles with a near-resonance laser. Using this platform, we have in particular explored quantum magnetism, topological synthetic quantum matter, and a new light-matter interface. at Zoom
11 Jan 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., usually Staudingerweg 7, Minkowskiraum
Bastian Schlag, Institut für Physik
at Zoom for now

12 Jan 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
 Zheng-Tian Lu, University of Science and Technology of China The long-lived noble-gas isotope 81Kr is the ideal tracer for water and ice with ages of 105 - 106 years, a range beyond the reach of 14C. 81Kr-dating, a concept pursued over the past five decades, is finally available to the earth science community at large. This is made possible by the development of the Atom Trap Trace Analysis (ATTA) method, in which individual atoms of the desired isotope are captured and detected. ATTA possesses superior selectivity, and is thus far used to analyze the environmental radioactive isotopes 81Kr, 85Kr, and 39Ar. These three isotopes have extremely low isotopic abundances in the range of 10-17 to 10-11, and cover a wide range of ages and applications. In collaboration with earth scientists, we are dating groundwater and mapping its flow in major aquifers around the world. We are also dating old ice from the deep ice cores of Antarctica, Greenland, and the Tibetan Plateau. For an update on this worldwide effort, please google “ATTA Primer”. at Recording of the presentation
13 Jan 2021

### PRISMA+ Colloquium

###### Institut für Physik13:00 Uhr s.t., None
 Daniele Guffanti, Institute of Physics, JGU Mainz The Sun, as all the other stars, is fueled for most of its life by the fusion of hydrogen into helium taking place in its core. Neutrinos produced in such reactions are the only direct probe to the innermost part of our star and real time messengers of its engine. Decades of experimental and phenomenological efforts allowed us to study in detail the driving energy production mechanism in the Sun, the proton-proton chain, which is responsible for ~99% of the Sun luminosity. The fusion processes accounting for the remaining 1% are believed to be catalyzed by the presence of Carbon, Nitrogen and Oxygen (CNO-cycle) in the Sun interior, but a direct evidence of the occurrence of such mechanism was still missing. After years-long efforts, the Borexino experiment at the Gran Sasso National Laboratories has recently reported the first direct observation of solar neutrinos produced in the CNO-cycle. In this talk I will present the Borexino findings and I will discuss the importance of CNO neutrinos for astrophysics and for our understanding of the Sun, particularly in connection to its chemical composition. at Zoom
14 Jan 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14 Uhr c.t., None
 Tanya S. Roussy, M.A., JILA (University of Colorado Boulder & NIST) Over the past few decades, accelerators have been the traditional venue for new particle discoveries – but the paradigm is shifting. Accelerator energies are likely to remain on a plateau for some time, while atomic physics & precision measurement are in a remarkable period of progress. Some limits have advanced by a factor of 100 in less than 10 years, and laser technologies are being refined to exquisite levels. New Physics searches are already an established avenue in the atomic physics field; from atomic parity violation, to EDM searches, to equivalence principle tests. Happily, many of these platforms are well-suited to do double-duty as broadband dark matter searches. In this talk, I will explain the basics of our unique trapped-ion electron EDM search, how we used our recent data to constrain the gluon to axion-like particle coupling over seven mass decades, and how we solved some important methodological issues along the way. at Zoom

### Theoriekolloquium

###### Die Dozierenden der Theoretischen Physik16:00 Uhr s.t., usually Newton-Raum, Staudinger Weg 9, 01-122
 Dries Sels, New York University Recent technological advances have put us at the brink of having access to small scale quantum computers capable of solving problems that cannot be tackled with classical computers. A limited number of algorithms have been proposed and their relevance to real world problems is a subject of active investigation. Solving problems relevant to chemistry are expected to be the first successful applications of quantum computers. In this talk, I will discuss a particular problem that can be solved efficiently on quantum computers: model inference for nuclear magnetic resonance (NMR) spectroscopy. I will give a broad introduction to quantum computing and NMR metabolomics assuming no prior knowledge of the subject. at Zoom
15 Jan 2021

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., via Zoom
Nathalie Katsonis, University of Groningen, The Netherlands

18 Jan 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., usually Staudingerweg 7, Minkowskiraum
Eftychia Tzovara, Institut für Physik
at Zoom for now

19 Jan 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
 Bernadett Weinzierl, University of Vienna, Austria Aerosol particles are an important constituent of the global climate system. They not only affect the atmospheric radiation budget through scattering and absorption of solar radiation and through their role as cloud/ice nuclei but also impact air quality and human health. Both natural and human processes contribute to the global aerosol load. Whereas coarse‐mode aerosol (>1 μm diameter) mainly originates from natural aerosol sources, fine mode aerosol is frequently associated with human activities. Although substantial effort has been undertaken in the last decades to improve our knowledge about aerosols and their role in the global climate system, aerosol‐cloud‐radiation interactions still pose the largest uncertainty to estimates and interpretations of the Earth’s changing energy budget (IPCC, 2013). In order to decrease these uncertainties, research is necessary. Thereby, research aircraft like the German Aerospace Center (DLR) Falcon and the NASA DC‐8 provide unique platforms to study the horizontal and vertical distribution of aerosols and their microphysical, chemical and optical properties. In this talk, I will introduce aerosols in general, and discuss their effects on the atmosphere and climate. Furthermore, I will show selected results from airborne field experiments with the DLR research aircraft Falcon and the NASA research aircraft DC8 studying the long‐range transport of mineral dust (SALTRACE project), the global distribution of coarse mode aerosols (ATom project), and aerosol mixtures in the Eastern Mediterranean (A‐LIFE project). at Zoom

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t., None
 Danny van Dyk, TUM, Munich I will discuss theory predictions for exclusive b->s ll decays within the SM and beyond, with emphasis on the hadronic matrix elements. There are two categories of these matrix elements: local form factors, and nonlocal contributions arising from e.g. four-quark operators. I will report the status and report recent progress from QCD-based methods on the non-local hadronic matrix elements arising from intermediate charm states. A particular focus will be a recent derivation of a dispersive bound on the non-local matrix element as discussed in arXiv:2011.09813.Slides here... at Zoom
20 Jan 2021

### PRISMA+ Colloquium

###### Institut für Physik13:00 Uhr s.t., None
Jens Erler, JGU Mainz
at Zoom

21 Jan 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14 Uhr c.t., None
 Prof. Dr. Hatice Altug, EPFL Lausanne, CH New health initiatives with global healthcare, precision medicine and point-of-care diagnostics are demanding breakthrough developments in biosensing and bioanalytical tools. Current biosensors are lacking precision, bulky, and costly, as well as they require long detection times, sophisticated infrastructure and trained personnel, which limit their application areas. My laboratory is focused on to address these challenges by exploiting novel optical phenomena at nanoscale and engineering toolkits such as nanophotonics, nanofabrication, microfluidics and data science. In particular, we use photonic nanostructures based on plasmonics and dielectric metasurfaces that can confine light below the fundamental diffraction limit and generate strong electromagnetic fields in nanometric volumes. In this talk I will present how we exploit nanophotonics and combine it with imaging, biology, chemistry and data science techniques to achieve high performance biosensors. I will introduce ultra-sensitive Mid-IR biosensors based on surface enhanced infrared spectroscopy for chemical specific detection of molecules, large-area chemical imaging and real-time monitoring of protein conformations in aqueous environment. Next, I will describe our effort to develop ultra-compact, portable, rapid and low-cost microarrays and their use for early disease diagnostics in real-world settings. Finally, I will highlight label-free optofluidic biosensors that can perform one-of-a-kind measurements on live cells down to the single cell level, and provide their prospects in biomedical and clinical applications. at Zoom

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau18:00 Uhr s.t., None
Scott Shell, UCSB, USA
at Zoom

25 Jan 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., usually Staudingerweg 7, Minkowskiraum
Florian Thomas, Institut für Physik
at Zoom for now

26 Jan 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
 Viola Priseman, Max-Planck-Institution , Göttingen, Germany How can we deal with a pandemic like COVID-19 so that neither health nor society and the economy suffer unnecessarily? We inferred the effectiveness of interventions, and developed effective containment strategies. Interestingly, we have identified a metastable state that not only stabilizes low case numbers, but also significantly reduces the necessary contact reductions and lockdowns. In this talk, we will introduce the underlying models, explore different containment strategies, and discuss recent developments. at Recording of the presentation

### Theorie-Palaver

###### Institut für Physik17:30 Uhr s.t., MITP seminar room
 Zhengkang (Kevin) Zhang, Caltech Matching a UV theory onto a low-energy EFT can be efficiently accomplished with functional methods. The functional approach is conceptually appealing: all calculations are performed within the UV theory at the matching scale, and no prior determination of an EFT operator basis is required. In this talk, I will present a simple prescription for functional matching up to one loop order, which accommodates any relativistic UV theory that contains generic interactions among scalar, fermion and vector fields. I will also introduce STrEAM (SuperTrace Evaluation Automated for Matching), a Mathematica package that helps streamline the procedure.Slides here... at Zoom
28 Jan 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14 Uhr c.t., None
 Univ.-Prof. Dr. Tanja Mehlstäubler, Physikalisch-Technische Bundesanstalt, Braunschweig Single trapped and laser-cooled ions in Paul traps allow for a high degree of control of atomic quantum systems. They are the basis for modern atomic clocks, quantum computers and quantum simulators. Our research aims to use ion Coulomb crystals, i.e. many-body systems with complex dynamics, for precision spectroscopy. This paves the way to novel quantum clocks for applications such as relativistic geodesy and improved navigation. The high-level of control of self-organized Coulomb crystals also opens up a fascinating insight into the non-equilibrium dynamics of coupled many-body systems, displaying atomic friction and symmetry-breaking phase transitions. We discuss the creation of topological defects in 2D crystals and present recent results on the study of tribology and transport mediated by the topological defect. at Zoom
29 Jan 2021

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., via Zoom
 Emanuela Zaccarelli, University of Rome Microgels are soft particles individually made by cross-linked polymer networks which are nowadays widely used as a colloidal model system because of their swelling properties and their responsivity to external control parameters such temperature or pH. In this talk I will briefly illustrate the protocol that we recently developed to synthesize microgels in-silico, providing a realistic description of the particles. I will then focus on the calculation of their elastic properties and of the effective interactions in bulk and at liquid-liquid interfaces and compare the results with the famous Hertzian model. While we find that the validity of such model in bulk is fairly limited[1], when microgels are adsorbed at interfaces, they effectively behave as 2D elastic disks. Such soft interactions are predicted to show a reentrant liquid-glass-liquid behavior at high densities in a range of experimentally accessible conditions, namely for small and loosely cross-linked microgels[2]. [1] L. Rovigatti, N. Gnan, A. Ninarello and EZ, Macromolecules (2019). [2] F. Camerin, N. Gnan, J. Ruiz-Franco, A. Ninarello, L. Rovigatti and EZ, Phys. Rev. X (2020).
01 Feb 2021

at Zoom for now

02 Feb 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
 Andy Brown, ECMWF, Reading, Great Britain Accurate weather predictions are of huge value to society, being used to inform actions that save lives and money. They are also a scientific success story, with global 5 day forecasts today being as accurate as 2 days forecasts of 30 years go. This talk will summarize the approach used, recent progress and future research and development priorities. These include further advances in understanding and modelling of multiple components of the Earth system (eg atmopshere, land, ocean and sea-ice), developments in observations and data assimilation methods, and bringing together the physical and computational science communities to take full advantage of new supercomputer architectures and advances in data science. at Recording of the presentation

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t., None
 Anders Eller Thomsen, University of Bern RG functions are used in QFT to evolve theories between energy scales and are frequently used in both phenomenology and theory. Starting at the 3-loop order, certain RG functions start exhibiting poles in the dimensional expansion, contrasting with the expectation that they should be finite. In this talk, I will clarify how this issue can be understood and how it is linked with an ambiguity in choosing renormalization constants that goes beyond a simple choice of renormalization scheme. The discussion will lead to a preferred prescription for the RG functions, which guarantees finiteness.Slides here... at Zoom
03 Feb 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
 Oleg Tchernyshyov, Johns Hopkins University https://www.spice.uni-mainz.de/2021/01/13/on-line-seminar-03-february-2021/ at Zoom and SPICE YouTube Channel
04 Feb 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14 Uhr c.t., None
 Prof. David Cassidy, University College London, UK Positronium (Ps) is a hydrogenic atom composed of an electron bound to a positron. Since it contains only leptons Ps is, for all practical purposes, a pure QED system, unaffected by nuclear structure effects. Also, being composed of a particle-antiparticle pair, Ps atoms are metastable, and may decay via self-annihilation, as well as through the usual radiative decay channels seen in regular atoms. The energy levels of Ps can be calculated to arbitrary precision (in principle), and precision spectroscopy of Ps can therefore be used to perform rigorous tests of bound-state QED theory. Moreover, since the theoretical description is limited only by the order of the calculations performed, rather than unknown physical constants or incalculable terms, any observed (and confirmed) disagreement with theory could indicate the existence of “new physics” such as particles or fields not currently included in the Standard Model. In this talk I will describe some new measurements of the Ps n = 2 fine structure, specifically 2 ^3S_1--> 2 ^3P_J (J = 0,1,2) transitions. The experiments were performed using a radioactive isotope-based positron beam coupled to a buffer gas/Penning trap. This allows positron pulses to be generated, which are converted into a dilute Ps gas with in vacuum an initial number density on the order of 10^6 cm^-3. A pulsed dye laser was used to optically excite atoms to the 2 ^3S_1 level, and microwave radiation was used to drive transitions to the 2 ^3P_J levels, which decay radiatively to the ground state before annihilation. The different annihilation decay rates of the ground and excited (S) states allows the fine structure transitions to be monitored via the time spectrum of the Ps annihilation radiation. We found that the measured J = 1 and J = 2 lineshapes exhibited significant asymmetries, whereas a symmetric lineshape was observed for the J = 0 transition. The observed asymmetries are not consistent with the most obvious quantum interference or line-pulling phenomena arising from nearby (off-resonant) transitions, and in the absence of a complete lineshape model we are therefore unable to determine the fine structure intervals for these transtions. Since the J = 0 lineshape did not exhibit any significant asymmetry it was possible to extract a value for the centre frequency: however, the obtained interval was found to disagree with theory by 2.77 MHz, which amounts to 4.5 standard deviations. No mechanism for a line shift of this magnitude has so far been identified. at Zoom

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau16:00 Uhr s.t., None
 Dr. Johannes Zierenberg, Max Planck Institute for Dynamics and Self-Organization, Göttingen, Germany Despite decades of research on disease spreading and epidemic outbreaks, the worldwide outbreak of COVID-19 was accompanied by scientific uncertainty resulting in insecure political actions. While scientific knowledge about the disease is initially uncertain until studied in detail, the worldwide available data on infected cases can be used to assess the current stage of the outbreak and allows for short term forecast of potential scenarios. Using a Bayesian framework even allows to incorporate and estimate parameter insecurity. I will present such an approach to infer spreading parameters during the initial outbreak of COVID-19 in Germany, show how to use it for short-term forecasts of potential scenarios, and argue that this approach adds a powerful tool to assist political decision making if the underlying assumptions and limitations are clearly communicated. I will further demonstrate how such models can be used to identify potential weak points in disease control, such as a limited tracing capacity. at Zoom
05 Feb 2021

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau10:30 Uhr s.t., None
Lukas Stelzl, Institute of Physics, JGU Mainz
at Zoom

08 Feb 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für PhysikSonderseminar: 12:30 Uhr s.t., usually Staudingerweg 7, Minkowskiraum
Thomas Honig, Institut für Physik
at Zoom for now

Sonderseminar

### SFB/TR49/SFB TRR 173 Spin+X-Kolloquium/TopDyn - Seminar experimentelle Physik der kondensierten Materie

###### SFB/TR49 - Prof. Dr. Elmers16:00 Uhr s.t., der Raum wird separat angekündigt
Ulrich Eckern, Augsburg University
at Zoom

09 Feb 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
 Michael Feindt, University of Karlsruhe This talk will review my personal history as elementary particle physics researcher (having started to work with neural networks at CERN in 1993), professor and entrepreneur (founder of Phi-T (2002) and Blue Yonder(2008)). It was always driven by what today is called Machine Learning and Artificial Intelligence, with emphasis on also predicting and taking advantage from knowledge about uncertainty. Today Blue Yonder, specialized on AI/ML and decision automation in the supply chain from Manufacturing to Retail, has more than 3500 large companies worldwide as customers and has delivered more than 1 trillion predictions. Examples from many different areas (physics, insurance, retail, supply chain) and experience gained over many years will show the tremendous value, but also the difficulties in bringing these methods into real life production in large scale international collaborations and companies - often against resistance. at Recording of the presentation

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t., MITP seminar room
 Riccardo Barbieri, SNS Pisa Motivated by the hierarchy problem and by the pattern of quark masses and mixings, I describe a picture of flavour physics that should give rise in a not too distant future to observable deviations from the SM in Higgs compositeness and/or in B-decays (if LFV confirmed) or perhaps even in supersymmetry, depending on the specific realization.Slides here... at Zoom
10 Feb 2021

### PRISMA+ Colloquium

###### Institut für Physik13:00 Uhr s.t., None
 Nicola Neri, Università di Milano Magnetic and electric dipole moments of fundamental particles provide powerful probes for physics within and beyond the Standard Model. For the case of short-lived particles these have not been experimentally accessible to date due to the difficulties imposed by their short lifetimes. A unique program of direct measurements of electromagnetic dipole moments of strange and charm baryons, and ultimately beauty baryons and the tau lepton, at the LHC is proposed. Novel experimental techniques have been developed, along with feasibility studies and projected sensitivities for different luminosity scenarios. at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Claudia Felser, MPI Chemical Physics of Solids
##### Magnetic Materials and Topology
at Zoom and SPICE YouTube Channel

11 Feb 2021

### Theoriekolloquium

###### Die Dozierenden der Theoretischen Physik16:00 Uhr s.t., usually Newton-Raum, Staudinger Weg 9, 01-122
 Ehud Altman, UC Berkeley From physics journals to campaign rallies, in this talk I'll try to explain what drives the remarkable popularity of the Sachdev-Ye-Kitaev model. In the first part I'll survey the evolution of this system from its origins as a solvable toy model of strongly interacting electrons to its current fame as a toy model of a quantum black hole. The latter came with Kitaev's discovery that, like a black hole, the low temperature dynamics of this model saturates the quantum bound on chaos. In the second part of the talk I will discuss how the model can be liberated from its status as a toy model by generalizing the physics from zero spatial dimensions to a genuine higher dimensional field theory. Time permitting I will discuss a specific application of such a field theory to describe unconventional quantum criticality in correlated electron systems. at Zoom

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14 Uhr c.t., None
 Dr. Stefan Ulmer, Ulmer Fundamental Symmetries Laboratory, RIKEN, Japan & CERN The Standard Model of particle physics is both incredibly successful and glaringly incomplete. Among the questions left open is the striking imbalance of matter and antimatter in our universe, which inspires experiments to compare the fundamental properties of matter/antimatter conjugates with high precision. The BASE collaboration at the antiproton decelerator of CERN is performing such high-precision comparisons with protons and antiprotons. Using advanced, ultra-stable, cryogenic particle traps and superconducting detectors with single particle sensitivity, we have performed the most precise measurement of the proton-to-antiproton charge-to-mass ratio with a fractional uncertainty of 69 parts per trillion [1]. In another measurement, we have invented a novel spectroscopy method, which allowed for the first ultra-high precision measurement of the antiproton magnetic moment with a fractional precision of 1.5 parts in a billion [2]. Together with our recent measurement of the proton magnetic moment [3] this improves the precision of previous experiments [4] by more than a factor of 3000. A time series analysis of this recent magnetic moment measurement furthermore enabled us to set first direct constraints on the interaction of antiprotons with axion-like particles (ALPs) [5], and most recently, we have used our ultra-sensitive single particle detection systems to derive narrow-band constraints on the conversion of ALPs into photons [6]. In my talk I will review the recent achievements of BASE and will outline strategies to further improve our high-precision studies of matter-antimatter symmetry. This outlook will involve the implementation of sympathetic cooling of antiprotons using quantum logic methods, the development of the transportable antiproton trap BASE-STEP, and will also review recent experimental progress towards 10-fold improved measurements of the antiproton properties. [1] S. Ulmer et al., Nature 524, 196 (2015). [2] C. Smorra et al., Nature 550, 371 (2017). [3] G. Schneider et al., Science 358, 1081 (2017). [4] J. DiSciacca et al., Phys. Rev. Lett. 110, 130801 (2013). [5] C. Smorra et al., Nature 575, 310 (2019). [6] J. A. Devlin et al., Phys. Rev. Lett., accepted (2021). S. Ulmer1, K. Blaum2, M. Bohman1,2, M. Borchert1,3, J. A. Devlin1,4, S. Erlewein1,2,4, M. Fleck1,5, C. Smorra1, M. Wiesinger1,2, C. Will2, E. Wursten5, Y. Matsuda6, C. Ospelkaus3, W. Quint6, J. Walz7,8, Y. Yamazaki1 1RIKEN, Ulmer Fundamental Symmetries Laboratory, Saitama, Japan; 2Max-Planck-Institut für Kernphysik, Heidelberg, Germany; 3Leibnitz University, Hannover, Germany; 4CERN, Geneva, Switzerland; 5The University of Tokyo, Tokyo, Japan; 6GSI - Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany; 7Johannes Gutenberg-Universität, Mainz, Germany; 8Helmholtz-Institut Mainz, Germany; at Zoom
12 Feb 2021

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., via Zoom
 Jens-Uwe Sommer, Leibniz-Institute of Polymer Research Dresden and TU Dresden The lower critical solution temperature (LCST) transition is introduced as type-II transition which results in many cases from competing effects of hydrogen bonding and hydrophobic behaviour of water-soluble polymers such as PEO and PNIPAm. As a consequence of the new type of phase separation a switch-like temperature response and phase coexistence is predicted for immobilized polymers such as polymer brushes or gels. I will give an introduction to simple theoretical concepts related with the type-II transition. Furthermore, I will demonstrate that mixed solvents can lead to type-II transitions with the prominent example of so-called co-nonsolvency [1]. Computer simulations and experiments confirm the basic conclusions from the theoretical model for polymer brushes [2,3]. Moreover, this phase transition is most likely driving the formation of protein-RNA-droplets in living cells. Using atomistic simulations it is shown for the example of PEO that stretching of the conformations can induce a phase transition far below the LCST which can be explained by the release of hydrogen bonds in the stretched state of PEO [4]. An aquamelt is introduced in general as a system where stretching/flow induces phase separation and subsquent crystallization, very similar to the process of spider-silk spinning in Nature. Aquamelts break the paradigm that solution properties of polymers are independent of conformation statistics. [1]J.-U. Sommer, Gluonic and Regulatory Solvents: A Paradigm for Tunable Phase Segregation in Polymers, Macromolecules 51, 3066 (2018); Adsorption-Attraction Model for Co-Nonsolvency in Polymer Brushes, Macromolecules 50, 2219 (2017) [2]A. Galuschko and J.-U. Sommer, Co-Nonsolvency Response of a Polymer Brush: A Molecular Dynamics Study, Macromolecules 52, 4120 (2019) [3]H. Yong, E. Bittrich, P. Uhlmann, A. Fery and J.-U. Sommer, Co-nonsolvency transition of poly(N-isopropylacrylamide) brushes in a series of binary mixtures, Macromolecules 52, 6285 (2019) [4]S. Donnets and J.-U. Sommer, J. Phys. Chem. B 122, 392 (2018)Slides here... Link: https://zoom.us/j/98197416231?pwd=c3ZnV0V6TDhsbkkwMnVDbTVWRG41dz09
16 Feb 2021

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t., MITP seminar room
 Nick Evans, Southampton U. I review arguments that chiral symmetry breaking is triggered when the quark bilinear condensate's dimension passes through one. This is supported by gap equations and more recently holographic models. Confinement may then be a separate property of the pure Yang-Mills theory below the scale of the dynamically generated quark mass, occurring at the scale of the pole in the deep IR running. Theories with more than one representation may have gaps between the condensation scales for the different representations with confinement below the lowest scale. Here, we use perturbative results for the running of the gauge coupling and gamma in asymptotically free SU(Nc) gauge theories with matter in higher dimension representations to seek the best candidate theories where confinement and chiral symmetry breaking can be maximally separated.Slides here... at Zoom
17 Feb 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Olena Gomonay, JGU
##### Seeing or listening: magnetoelastic effects in antiferromagnetic textures
at Zoom and SPICE YouTube Channel

19 Feb 2021

at Zoom

24 Feb 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Sergej Demokritov, University of Münster
##### Spatio-Temporal Dynamics of Magnon Bose-Einstein Condensates
at Zoom and SPICE YouTube Channel

26 Feb 2021

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau18:00 Uhr s.t., None
Marina Guenza, Dept. of Chemistry and Biochemistry, University of Oregon, USA
at zoom

03 Mar 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Ulrich Rößler, IFW Dresden
##### Improper Dyzaloshinskii spirals and metamagnetic textures - and where to look for them
at Zoom and SPICE YouTube Channel

05 Mar 2021

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau14:00 Uhr s.t., None
Frank Siebers, Institute of Physics, JGU
##### Dynamics of Light Driven Circle Walkers
at Zoom

Master Colloquium

10 Mar 2021

### SPICE-Spin+X Seminar

##### All-optical control of magnetism: from fundamentals to brain-inspired computing concepts
at Zoom and SPICE YouTube Channel

17 Mar 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Henning Sirringhaus, University of Cambridge
##### Charge and Spin transport physics of organic semiconductors
at Zoom and SPICE YouTube Channel

24 Mar 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Christian Back, TUM
##### Optical and Electrical Detection of Spin-Orbit Fields
at Zoom and SPICE YouTube Channel

31 Mar 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Igor Mazin, George Mason University
##### Dynamic generation of scalar chirality and topological Hall effect in spiral magnets
at Zoom and SPICE YouTube Channel

07 Apr 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Silvia Viola-Kusminskiy, MPL
##### Quantum magnonics: Quantum optics with magnons
at Zoom and SPICE YouTube Channel

12 Apr 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., usually Staudingerweg 7, Minkowskiraum
Timo Graffe, Universität Mainz
at Zoom for now

13 Apr 2021

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t., MITP seminar room
 Raffaele Tito D'Agnolo, IPhT Saclay I will discuss settings where the Higgs mass squared affects the vacuum expectation value of local operators and can thus act as a “trigger” of new cosmological dynamics. This triggering mechanism underlies several existing solutions to the hierarchy problem that trace the origin of the weak scale to the early history of the Universe. Thinking about these solutions more systematically from the point of view of weak scale triggers allows to understand their common predictions, to find new solutions and to identify unexpected physics related to naturalness in a rather model-independent way. As an example I discuss a BSM trigger in a Two Higgs Doublet Model and show how it can be used to link the tuning of the Higgs mass to that of the cosmological constant. This weak scale trigger demands the existence of new Higgs states necessarily comparable to or lighter than the weak scale, with no wiggle room to decouple them.Slides here... at Zoom

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
 Hartmut Wittig und Martin Fertl, University of Mainz The long-persisting discrepancy between the Standard Model prediction of the anomalous magnetic moment of the muon (aµ) and its latest measurement provides an intriguing hint to new physics. Since 2017, the Muon g − 2 Theory Initiative has assessed the theoretical prediction for aµ, focusing on the contributions from the strong interaction, which account for the dominant part of the uncertainty. The latest estimate for the Standard Model prediction, which was published in a recent White Paper, has failed to resolve the discrepancy with the experimental measurement at Brookhaven National Laboratory, which stands at 3.7 standard deviations. At Fermi National Accelerator Laboratory, USA, the Muon g-2 collaboration is performing a new measurement of aµ aiming at an ultimately fourfold smaller uncertainty than achieved with the predecessor experiment. To extract the value of aµ a clock comparison experiment is performed with spin-polarized muons confined in a superbly controlled electric and magnetic field environment. The deviation of the Larmor from the cyclotron frequency, the anomalous spin precession frequency, is determined while a high-precision measurement of the magnetic field environment is performed using nuclear magnetic resonance techniques. We will provide an introduction to the current theory prediction before we will present and discuss the first results of the FNAL experiment from its 2018 science run. at Recording of the presentation
14 Apr 2021

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., None
 Thomas Speck, Johannes Gutenberg University TBA at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Jörg Wunderlich, Regensburg University
##### Magneto-Seebeck microscopy of spin-orbit-torque driven domain wall motion in a collinear antiferromagnet
at Zoom and SPICE YouTube Channel

15 Apr 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Prof. Dr. Peter Hommelhoff, Friedrich-Alexander-Universität Erlangen-Nürnberg Free electrons are used in a plethora of instruments, ranging from electron microscopes to particle accelerators and modern light sources for decades. Yet, fundamentally new concepts are surfacing, taking advantage of electrons in an entirely new way, mainly based on quantum mechanical and nanophotonics concepts. In this talk, I will show recent results towards interaction-lean imaging with electrons and on-chip control of electrons. These results bring us closer to a quantum electron microscope and to a particle accelerator on a chip. at Zoom
19 Apr 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., usually Staudingerweg 7, Minkowskiraum
Vincent Roy, Universität Mainz
at Zoom for now

### SFB/TR49/SFB TRR 173 Spin+X-Kolloquium/TopDyn - Seminar experimentelle Physik der kondensierten Materie

###### SFB/TR49 - Prof. Dr. Elmers16:00 Uhr s.t., None
Andrii Chumak, University of Vienna, Austria
at Zoom

20 Apr 2021

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t., MITP seminar room
 Xiaofeng Xu, Bern University Canonical Feynman integrals are of great interest in the study of scattering amplitudes at the multi-loop level. We propose to construct d log-form integrals of the hypergeometric type, treat them as a representation of Feynman integrals, and project them into master integrals using intersection theory. This provides a constructive way to build canonical master integrals whose differential equations can be solved easily. We use our method to investigate both the maximally cut integrals and the uncut ones at one and two loops, and demonstrate its applicability in problems with multiple scales.Slides here... at Zoom

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
 Mehran Kardar, Massachusetts Institute of Technology, Cambridge, USA Affinity maturation (AM) is the process through which the immune system evolves antibodies (Abs) which efficiently bind to antigens (Ags), e.g. to spikes on the surface of a virus. This process involves competition between B-cells: those that ingest more Ags receive signals (from T helper cells) to replicate and mutate for another round of competition. Modeling this process, we find that the affinity of the resulting Abs is a non-monotonic function of the target (e.g. viral spike) density, with the strongest binding at an intermediate density (set by the two-arm structure of the antibody). We argue that, to evade the immune system, most viruses evolve high spike densities (SDs). An exception is HIV whose SD is two orders of magnitude lower than other viruses. However, HIV also interferes with AM by depleting T helper cells, a key component of Ab evolution. We find that T helper cell depletion results in high affinity antibodies when SD is high, but not if SD is low. This special feature of HIV infection may have led to the evolution of a low SD to avoid potent immune responses early on in infection. Our modeling also provides guides for design of vaccination strategies against rapidly mutating viruses. at Recording of the presentation
21 Apr 2021

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., None
 Angelika Kühnle, Bielefeld University TBA at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Chiara Ciccarelli, University of Cambridge
##### Spin transport in a conventional superconductor
at Zoom and SPICE YouTube Channel

22 Apr 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Prof. Dr. Konrad Lehnert, JILA, University of Colorado, Boulder, USA Can emerging quantum information technologies, in some way, improve or enhance searches for fundamental physical phenomena? Indeed, the use of optical squeezing in gravitational wave observatories is a beautiful example that they can. In addition to this one prominent example, the search for dark matter may offer several other near-term experiments that can, and perhaps must, use enhanced quantum sensing methods. In particular detail, I’ll discuss the case of searching for a hypothetical dark matter particle known as the axion and accelerating the search using quantum squeezing approaches. at Zoom
26 Apr 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., usually Staudingerweg 7, Minkowskiraum
Jan Weldert, Universität Mainz
at Zoom for now

27 Apr 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
 Jason Detwiler, University of Washington, USA Neutrinos are known for their elusive nature due to their extremely small cross section for scattering off of individual nucleons inside of nuclei. However they can also undergo billiard-ball-like coherent elastic scattering off of entire nuclei, with a greatly enhanced cross section. This coherent elastic neutrino-nucleus scattering (CEvNS) is an important process in core-collapse supernovae, and can also be used for astrophysical and terrestrial neutrino detection. The coherence of the interaction can also amplify potential non-standard interactions between neutrinos and quarks, making it an ideal mode for testing as-yet unprobed physics beyond the Standard Model. Although CEvNS was predicted in 1974, its first observation was only recently made in 2017 by the COHERENT collaboration, leveraging decades of Dark Matter detector R&D that has yielded technologies with sufficient sensitivity to observe the ultra-faint nuclear recoils that are the only signatures of the interaction's occurrence. COHERENT's discovery was also enabled by its nearly ideal pulsed source of pion-decay neutrinos: the beam dump of the Spallation Neutron Source at Oak Ridge National Laboratory. In this talk, I will discuss the physics of CEvNS and its challenging measurement. I'll describe COHERENT's first observation of CEvNS using the world's first hand-held neutrino detector, a CsI scintillating crystal. I will then detail our more recent first observation of CEvNS with argon using a scintillating volume of liquid Ar, including our updated sensitivity to non-standard neutrino interactions and other physics. I'll also describe our plans to field two more detectors using NaI scintillating crystals as well as an array of germanium radiation detectors, and our longer term plans to build multiple ton-scale experiments at a new beam stop with significantly improved sensitivity. at Slides
28 Apr 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Ulrich Nowak, University of Konstanz
##### Spin dynamics: the Landau-Lifshitz equation and beyond
at Zoom and SPICE YouTube Channel

### PRISMA+ Colloquium

###### Institut für Physik13:00 Uhr s.t., None
Javier Fuentes, JGU
at Zoom

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., None
Pol Besenius, Johannes Gutenberg University
at Zoom

29 Apr 2021

### Theoriekolloquium

###### Die Dozierenden der Theoretischen Physik16:00 Uhr s.t., None
 Joaquin Rodriguez-Nieva, Stanford University TBA Topic: Th. Kolloquium Time: Apr 29, 2021 04:00 PM Amsterdam, Berlin, Rome, Stockholm, Vienna Join Zoom Meeting https://zoom.us/j/95899860316?pwd=dHBiREgyNnBOUml3QzNBSzUxZGJmQT09 Meeting ID: 958 9986 0316 Passcode: 090910 at Zoom

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Prof. Dr. Andreas Hemmerich, Institut für Laser-Physik, Universität Hamburg I will review our recent research on time crystal dynamics in an atom-cavity system. In contrast to discrete time crystals in driven closed systems, where dissipation constitutes an undesired obstacle, I will discuss an ansatz, where tailored dissipation and fluctuations, induced via controlled coupling to a suitable environment, stabilize time crystal dynamics. The central signature in our implementation in a driven open atom-cavity system is a period doubled switching between distinct chequerboard density wave patterns, induced by the interplay between controlled cavity-dissipation, cavity-mediated interactions and external driving. We demonstrate the robustness of this dynamical phase against system parameter changes and temporal perturbations of the driving. at Zoom
30 Apr 2021

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau10:30 Uhr s.t., None
Maike Jung, Institute of Physics, JGU Mainz
at Zoom

04 May 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
 Gia Dvali, Max Plank Institute of Physics, Munich Understanding the origin of hierarchies is one of the main driving forces of today's fundamental research. The well-known examples are provided by the hierarchy between the weak and Planck scales, the hierarchy between neutrino and electron masses and the hierarchy between the Planck scale and the vacuum energy of the present Universe. Sometimes these puzzles are classified as so-called naturalness problems". Historically, in the case of proton/pion mass hierarchy, such questions led to advances that changed modern particle physics. In this talk we review certain representative examples when the hierarchy can be taken as a serious indication for new physics. We also review cases when a seeming naturalness problem is nullified by consistency of the theory. We give an example of the celebrated naturalness puzzle of the cosmological term. This however turns out to be fictitious, since the consistency of the S-matrix formulation demands that the cosmological constant is excluded from the energy budget of our Universe. at Recording of the presentation

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t., None
 Admir Greljo, Bern U. Recent R(K) update from the LHCb experiment at CERN reinforced the tension of B-meson decays into muons. Shortly after, the Muon g-2 experiment at Fermilab strengthened the tension in the muon anomalous magnetic moment. Immense theoretical and experimental work is still needed to possibly establish the existence of new physics, nonetheless, we can already ask relevant questions. Can muon anomalies be coherently addressed in models beyond the SM, and if so, where else should we look for confirmation? I will discuss minimal extensions of the SM based on 2103.13991.Slides here... at Zoom
05 May 2021

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., via Zoom
Markus Mezger, University of Vienna, MPI-P

06 May 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Prof. Dr. Ignacio Cirac, Max-Planck-Institut für Quantenoptik, Garching Quantum many-body systems are very hard to simulate, as computational resources (time and memory) typically grow exponentially with system size. However, quantum computers or analog quantum simulators may perform that task in a much more efficient way. In this talk, I will first review some of the quantum algorithms that have been proposed for this task and then explain the advantages and disadvantages of analog quantum simulators. I will also describe theoretical proposals to solve different quantum simulation problems with cold atoms in optical lattices. at Zoom
11 May 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
 Achim Stahl, RWTH Aachen, Germany Gravitational waves opened a new window into the universe. The current generation of gravitational wave detectors demonstrated the existence of gravitational waves and made a number of highly interesting discoveries. In parallel with their operation we are developing a new generation of telescopes with a sensitivity goes beyond the final sensitivity of the current telescopes by at least an order of magnitude. The Einstein Telescope will be the European project of the new generation. After an introduction of gravitational waves and a few highlights from the current observation runs, I will discuss the perspectives and technologies necessary to improve their performance. I will introduce the Einstein Telescope and present a few example of the science we might expect at Recording of the presentation

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t., None
 Lorenzo Ubaldi, SISSA, Trieste A scalar inflaton coupled to a dark photon can produce a large density of the latter. I will discuss the mechanism underlying this production, which takes place mostly at the end of inflation. After reheating, the dark photons are relativistic at first and then redshift to non relativistic. Their energy density today can match that of the observed dark matter in a wide region of parameters of the model. It is interesting to study in detail also the dark photon power spectrum and its cosmic evolution, which predicts a clumpy nature of this dark matter candidate, possibly useful for experimental searches.Slides here... at Zoom
12 May 2021

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., None
Michael Kappl, MPI-Polymer Research
at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Ulrich Nowak, Konstanz University
##### Spin dynamics: the Landau-Lifshitz equation and beyond
at Zoom and SPICE YouTube Channel

17 May 2021

### SFB/TR49/SFB TRR 173 Spin+X-Kolloquium/TopDyn - Seminar experimentelle Physik der kondensierten Materie

###### SFB/TR49 - Prof. Dr. Elmers16:00 Uhr s.t., None
Jeffrey McCord, Kiel University
at Zoom

18 May 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
Kathrin Valerius, Karlsruher Institute of Technology, Germany
##### News on the Neutrino-Mass Measurement
at Recording of the presentation

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t., MITP seminar room
 Florian Goertz, Max-Planck-Institut für Kernphysik, Heidelberg In this talk, we present a minimal viable scenario that unifies the gauge symmetries of the SM and their breaking sector. Our Gauge-Higgs Grand Unification setup employs 5D warped space with a SU(6) bulk gauge field that includes both a SU(5) grand unified theory (GUT) and a Higgs sector as a scalar component of the 5D vector field, solving the hierarchy problem. By appropriately breaking the gauge symmetry on the boundaries of the extra dimension the issue of light exotic new states, appearing generically in such models, is eliminated and the SM fermion spectrum is naturally reproduced. The Higgs potential is computed at one-loop, finding straightforward solutions with a realistic mh = 125 GeV. The problem of proton decay is addressed by showing that baryon number is a hidden symmetry of the model. The presence of a scalar leptoquark and a scalar singlet is highlighted, which might play a role in solving further problems of the SM, allowing for example for electroweak baryogenesis. Finally, the X and Y gauge bosons from SU(5) GUTs are found at collider accessible masses, opening a window to the unification structure at low energies.Slides here... at Zoom
19 May 2021

### PRISMA+ Colloquium

###### Institut für Physik13:00 Uhr s.t., None
 Iwona Grabowska-Bold, Krakow The Large Hadron Collider (LHC) is capable of accelerating proton and nucleus beams to ultra-relativistic velocities and provides collisions at unprecedented center-of-mass energy. The physics programme spans from precision measurements of processes predicted by the Standard Model (SM), through searches and tests of multiple theories beyond SM to studies of the quark-gluon plasma - a deconfined state of quarks and gluons. Although, most of the year the LHC collides proton beams, it also provides heavy-ion (HI) collisions. All four experiments, ALICE, ATLAS, LHCb and CMS, have HI physics programmes established based on lead-lead, proton-lead, and reference proton-proton collisions. In this talk basic concepts of ultra-relativistic HI physics will be introduced. Physics opportunities with two extreme categories of centrality classes (central and ultra-peripheral) will be discussed. The selection of recent measurements from ALICE, ATLAS, CMS and LHCb experiments will be reviewed. A talk will be concluded with a brief discussion of the future HI data taking. at Zoom

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., None
Arash Nikoubashman, Johannes Gutenberg University
at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Karin Everschor-Sitte, JGU
##### Magnetic skyrmions for unconventional computing and revealing latent information
at Zoom and SPICE YouTube Channel

20 May 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Prof. Dr. Ralf Röhlsberger, Helmholtz Institut Jena/Friedrich-Schiller Universität Jena The remarkable development of accelerator-driven light sources such as synchrotrons and X-ray lasers with their highly brilliant X-rays has brought quantum and nonlinear phenomena at X-ray energies within reach. X-ray photonic structures like cavities and superlattices are employed as new laboratory to realize quantum optical concepts at x-ray energies. The prime candidates to be chosen as atomic emitters in this field are Mössbauer isotopes. Their extremely small resonance bandwidth facilitates to probe fundamental phenomena of the light-matter interaction like the observation of single-photon superradiance and the collective Lamb shift as well as electromagnetically induced transparency with nuclei. Employing higher-order coherences of x-ray fields in the spirit of Glauber could even lead to novel concepts for quantum imaging at x-ray energies. at Zoom
26 May 2021

at Zoom

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., None
Kurt Kremer, MPI-Polymer Research
at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
James G. Analytis, Berkeley
##### Antiferromagnetic Switching Driven by the Collective Dynamics of Correlated Spin Textures
at Zoom and SPICE YouTube Channel

27 May 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Dr. Christian Sanner, JILA, University of Colorado, Boulder, USA Can Fermi quantum statistics be used to manipulate the radiative properties of atomic emitters? Is it possible to extend the natural lifetime of an electronically excited atom by placing it inside a bath of quantum-degenerate ground-state atoms? I will report on an experiment that demonstrates how a Fermi sea can block the spontaneous decay of an excited atom. This striking manifestation of Fermi statistics connects for the first time the fundamental radiative property of atoms to their motional degrees of freedom subject to quantum statistics. Quantum engineering the atom-photon coupling opens up new perspectives for optical clocks, which face spontaneous decay as a fundamental decoherence mechanism. at Zoom
31 May 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., usually Staudingerweg 7, Minkowskiraum
Manuel Hohmann, Institut für Physik
at Zoom for now

01 Jun 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
Katia Parodi, University of Munich, Germany
at Attachement

02 Jun 2021

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., None
Nathalie Katsonis, University of Groningen, The Netherlands
at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Giovanni Finocchio, University of Messina
##### Spintronic microwave and THz detectors: state-of-the art and future!
at Zoom and SPICE YouTube Channel

08 Jun 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
 Jens Erler, University of Mainz Half a century ago the foundations underpinning the gauge theories of the strong, weak and electromagnetic interactions had been laid out, and the age of precision calculations for its tests and the determination of its parameters could begin. We recall some of the history with an emphasis on the role played by electroweak precision tests. While in the past theoretical ideas have often preceded experimental discoveries, the years and decades ahead of us are in desperate need of experimental guidance. at Zoom

### Theorie-Palaver

###### Institut für Physik17:30 Uhr s.t., MITP seminar room
 Ben Safdi, Berkeley The quantum chromodynamics axion and axion-like particles are some of the most sought-after beyond the Standard Model particles at present because of their possible connections with the strong-CP problem, dark matter, and ultraviolet physics such as Grand Unification and String Theory. Laboratory searches are underway around the world to search for these hypothetical particles, but certain regions of axion parameter space -- such as ultralight axions with weak couplings to matter -- are notoriously difficult to probe with terrestrial experiments, despite their theoretical motivations. However, axions in this part of the parameter space may be produced in abundance within compact stars such as white dwarfs and neutron stars. It has long been recognized that axion production in compact stars opens up a new pathway for them to cool. I will point out, however, that axions may also lead to novel X-ray signatures around these stars, whereby the axions are produced within the stellar cores and then convert to photons in the strong magnetic fields surrounding the stars. I will discuss recent data taken by the XMM-Newton and Chandra telescopes from nearby neutron stars and white dwarfs that provide some of the strongest probes to-date of axions by searching for these processes.Slides here... at Zoom
09 Jun 2021

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., None
Regine von Klitzing, Technical University of Darmstadt
at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Sangeeta Sharma, Max-Born-Institute
##### Ultrafast coupled charge, spin and nuclear dynamics: ab-initio description
at Zoom and SPICE YouTube Channel

### Theoriekolloquium

###### Die Dozierenden der Theoretischen Physik16:00 Uhr s.t., Newton-Raum, Staudinger Weg 9, 01-122
 Javier Argüello Luengo, ICFO Topic: Th. Kolloquium Time: Jun 9, 2021 04:00 PM Amsterdam, Berlin, Rome, Stockholm, Vienna Join Zoom Meeting https://zoom.us/j/94144055619?pwd=RWJyZE9yVm10K3VnajhIQVNGS1Y1UT09 Meeting ID: 941 4405 5619 Passcode: 090909 One tap mobile +496938079883,,94144055619# Germany +496950502596,,94144055619# Germany Dial by your location +49 69 3807 9883 Germany +49 695 050 2596 Germany +49 69 7104 9922 Germany +49 30 5679 5800 Germany Meeting ID: 941 4405 5619 Find your local number: https://zoom.us/u/aycp4DvK5 at Zoom
10 Jun 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Dr. Ana Maria Rey, JILA, NIST and University of Colorado, Boulder, USA I will discuss recent progress on the use of planar crystals with hundreds of ions as a platform for quantum simulation of spin and spin-boson models. The key idea is the use of a pair of lasers to couple two internal levels of the ions, that act as a spin½ degree of freedom, to the vibrational modes, phonons, of the crystal. In the regime when phonons do not play an active role in the dynamics and instead mediate spin-spin interactions we have been able to simulate Ising models with tunable-range spin couplings, and a many-body echo sequence, which we used to measure out-of-time-order correlations (OTOCs), a type of correlations that quantify the scrambling of quantum information across the system’s many-body degrees of freedom. In the regime when phonons actively participate we have been able to simulate the Dicke model, an iconic model in quantum optics which describes the coupling of a (large) spin to an oscillator and more recently realize a many-body quantum-enhanced sensor that can detect weak displacements and electric fields. Our system is the first to demonstrate an enhanced sensitivity resulting from quantum entanglement in a mesoscopic ion crystal with an improvement by a factor of 300 over prior classical protocols in trapped ions and more than an order of magnitude compared to state-of-the-art electrometers based on Rydberg atoms. Overall my talk plans to illustrate the great potential offered by trapped ion crystals not only as quantum simulators but also as feasible near-term detectors of dark matter. at Zoom
11 Jun 2021

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau10:30 Uhr s.t., None
Joseph F Rudzinski, MPIP, Mainz

14 Jun 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., usually Staudingerweg 7, Minkowskiraum
Alec Lindman, Institut für Physik
at Zoom for now

15 Jun 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
 Helmut Satz, University of Bielefeld, Germany In recent years, the study of swarm formation and structure has become a challenging field of research in which biology and physics overlap. It was shown that mathematical models of many identical components subject to simple interactions produce behavior patterns similar to those of swarms, as observed in high statistics measurments of starling flocks in Rome by the EU Starflag collaboration. Swarm behavior thus is an instance of selforganisation - there is no leader or formation plan. at Recording of the presentation

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t., None
 Matthew Reece, Harvard U. This talk will take the form of two mini-talks, which are loosely related in that both involve axion (or ALP) fields. First, I will discuss challenges when fitting the muon g-2 anomaly with axion-like fields in an EFT setting. I will argue that new particles are required near the weak scale to UV complete these models, and these are subject to experimental constraints and can also affect the muon g-2 directly. This is based on arXiv:2104.03267 with Manuel Buen-Abad, JiJi Fan, and Chen Sun. Second, I will discuss how axions interacting with abelian gauge fields acquire a potential through a nonperturbative, semiclassical effect involving loops of monopoles and dyons. This is an application of the Witten effect. This is based on arXiv:2105.09950 with JiJi Fan, Katie Fraser, and John Stout.Slides here... at Zoom
16 Jun 2021

at Zoom

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., None
Sigi Waldvogel, Johannes Gutenberg University
at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Andrew Kent, New York University
##### Electrical Generation of Spin Currents
at Zoom and SPICE YouTube Channel

17 Jun 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Dr. Silvia Viola-Kusminskiy, Max-Planck-Institute for the Science of Light, Erlangen In the last few years, a new field has emerged at the intersection between Condensed Matter and Quantum Optics, denominated “Quantum Magnonics”. This field strives to control the elementary excitations of magnetic materials, denominated magnons, to the level of the single quanta, and to interface them coherently to other elementary excitations such as photons or phonons. The recent developments in this field, with proof of concept experiments such as a single-magnon detector, have opened the door for hybrid quantum systems based on magnetic materials. This can allow us to explore magnetism in new ways and regimes, has the potential of unraveling quantum phenomena at unprecedented scales, and could lead to breakthroughs for quantum technologies. A predominant role in these developments is played by cavity magnonic systems, where an electromagnetic cavity, either in the optical or microwave regime, is used to enhance and control the interaction between photons and magnons. In this talk, I will introduce the field and present some theoretical results from our group which aim to push the boundaries of the current state of the art. at Zoom
18 Jun 2021

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau10:30 Uhr s.t., None
Maarten Brems, Institute of Physics, JGU Mainz

21 Jun 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., usually Staudingerweg 7, Minkowskiraum
Quirin Weitzel and Steffen Schönfelder, Prisma Detector Lab
at Zoom for now

### SFB/TR49/SFB TRR 173 Spin+X-Kolloquium/TopDyn - Seminar experimentelle Physik der kondensierten Materie

###### SFB/TR49 - Prof. Dr. Elmers16:00 Uhr s.t., None
Felix Tuczek, Christian-Albrechts-Universität zu Kiel
at Zoom

22 Jun 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
Horst Geckeis, Karlsruher Institute of Technology, Germany
##### Endlagerstätten in Deutschland
at Recording of the presentation

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t., None
 Keri Vos, Maastricht U. and Nikhef The determination of the CKM element Vcb from inclusive semileptonic b → c semileptonic decays has reached a high precision thanks to a combination of theoretical and experimental efforts. Moreover, the long standing Vcb puzzle, a discrepancy between inclusive and exclusive determinations seems to be disappearing. In this talk, I will discuss the story of Vcb and how to continue towards even higher precision focussing on the inclusive determination. Specifically, I discuss two new strategies to improve the precision. The first is based on reparametrization invariances, which allows including higher power-suppressed terms in the heavy-quark expansion (HQE), the second is a method to control background effects using the HQE.Slides here... at Zoom
23 Jun 2021

### PRISMA+ Colloquium

###### Institut für Physik17:00 Uhr s.t., None
 Svetlana Barkanova, Yury Kolomensky, Aleksandrs Aleksejevs, Ben Sheff, Memorial University, University of California Berkley, Memorial University, University of Michigan please note different time! at Zoom

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., None
Sebastian Seiffert, Johannes Gutenberg University
at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Vincent Baltz, SPINTEC
##### Spin And Charge Transport in Antiferromagnets
at Zoom and SPICE YouTube Channel

24 Jun 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Prof. Dr. Georg von Freymann, Technische Universität Kaiserslautern Terahertz spectroscopy has evolved over recent years from an interesting but technologically hard to address tool for fundamental studies to a technology with industrial applications. Closing the so-called terahertz gap is nowadays possible with ultrafast lasers from the optical side as well as with millimeter-wave-technology from the electronic side. After a brief review of the state-of-the-art I will focus on recent progress on terahertz cross-correlation-spectroscopy driven by a superluminescent light emitting diode and terahertz spectroscopy with undetected photons for which all terahertz spectral information is gained from visible photons. at Zoom
25 Jun 2021

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau10:30 Uhr s.t., None
Riccardo Martina, Department of Physics, University of Padua and Institute of Physics, JGU Mainz
at Zoom

29 Jun 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
 Norbert M. Linke, Joint Quantum Institute and Department of Physics, University of Maryland, College Park, MD 20742, USA Trapped ions give us a high degree of detailed control of their various quantum degrees of freedom, which has enabled a large number of experiments in quantum optics, quantum computing, simulation and networking as well as precision metrology and others. We present a quantum architecture consisting of a linear chain of trapped 171 Yb+ ions with individual laser beam addressing and readout. The collective modes of motion in the chain are used to efficiently produce entangling gates between any qubit pair. In combination with a classical software stack, this becomes in effect an arbitrarily programmable fully connected quantum computer. Over the past five years, we have employed this experiment to demonstrate a variety of quantum algorithms with the help of a community of academic partners, including cross-hardware comparisons with commercially developed systems and digital quantum simulations of models from high-energy physics and other areas. We also use the same level of control to study interesting quantum phenomena using the motional degrees of freedom directly, such as exotic para particles and Hubbard models of phonons. This talk will give recent highlights from both of these approaches and discuss improvements in trap technology for scaling up as well as other ideas for the future. at Recording of the presentation

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t., MITP seminar room
 Martin Winkler, Texas U. and Stockholm U. I will introduce Chain inflation as an alternative to slow roll inflation in which the universe undergoes a series of transitions between different vacua. The role of the inflaton can be played by an axion which tunnels from minimum to minimum in a quasiperiodic potential. I will determine the scalar power spectrum of chain inflation and show that it is fully consistent with a ΛCDM cosmology. Then I will turn to the Hubble tension, the apparent discrepancy between local measurements of the Hubble constant H0=74 km/s/Mpc and H0=67 km/s/Mpc inferred from the CMB. I will propose Chain Early Dark Energy - the low-energy analog of chain inflation - as a solution of the H0-tension and point to a connection to today's dark energy.Slides here... at Zoom
30 Jun 2021

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., None
Jens-Uwe Sommers, Leibniz Institute of Polymer Research, Dresden
at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Katharina Franke, FU Berlin
##### Building and investigating magnetic adatom chains on superconductors atom by atom
at Zoom and SPICE YouTube Channel

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t., Hörsaal 20 (Geb. 1 231, J.-J.-Becher Weg 14)
 Gilly Elor, University of Washington I will introduce a class of new mechanisms for low-scale baryogenesis and dark matter production that utilize the CP violation within Standard Model meson systems. Mesogenesis mechanisms operate at MeV scales and such, remarkably, are experimentally testable. I will first give an overview of B-Mesogenesis; in which baryogenesis proceeds through the oscillation and subsequent decay into a dark sector of neutral B mesons. B-Mesogenesis is testable at current hadron colliders and B-factors, and I will present results of recent studies that pave the way towards constraining (or discovering) this mechanism. Finally, I will present a recent proposal for D-Mesogenesis which relies on the CP violation of charged D mesons.Slides here... at Zoom
01 Jul 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Dr. Sven Herrmann, ZARM, Universität Bremen Following the accidental injection of the European GNSS satellites Galileo 5 and 6 into eccentric orbits in 2014, our group, as well as a second independent team, managed to use these satellites for a test of the general relativistic gravitational redshift. This was based on an analysis of three years of orbit and clock data from the Passive Hydrogen Masers on board of these satellites. In this talk I will present some aspects of this test of relativity and discuss also more recent progress on this topic in general. at Zoom

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau14:30 Uhr s.t., None
M. Lisa Manning, Department of Physics Physics, Syracuse University, New York, USA
at Zoom

02 Jul 2021

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau10:30 Uhr s.t., None
Paul Sonek, Institute of Physics, JGU Mainz

05 Jul 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., usually Staudingerweg 7, Minkowskiraum
Christian Matthé, Universität Mainz
at Zoom for now

06 Jul 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
 Ken Carslaw, University of Leeds, Great Britain Clouds containing a mixture of ice and supercooled water are expected to become more reflective in a warmer world as the ice is increasingly replaced by water. This response causes a negative “cloud-phase” climate feedback that acts to dampen global warming. In this presentation I will show that quantification of this cloud response hinges on understanding the properties of the rare particles that initiate ice formation – ice-nucleating particles. I will show results from modelling and observations that demonstrate the importance of these particles for cloud reflectivity. Substantial recent developments in our understanding of ice-nucleating particles from laboratory and field measurements now enable us to build reasonable global models of their distribution and to determine which properties matter for climate change. at Zoom

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t., None
 Tevong You, CERN We describe a new phenomenon in quantum cosmology: self-organised localisation. When the fundamental parameters of a theory are functions of a scalar field subject to large fluctuations during inflation, quantum phase transitions can act as dynamical attractors. As a result, the theory parameters are probabilistically localised around the critical value and the Universe finds itself at the edge of a phase transition. We illustrate how self-organised localisation could account for the observed near-criticality of the Higgs self-coupling, the naturalness of the Higgs mass, or the smallness of the cosmological constant.Slides here... at Zoom
07 Jul 2021

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., None
Hans-Jürgen Butt, MPI-Polymer Research
at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Philipp Pirro, TUK
##### Neuromorphic magnon-spintronic networks
at Zoom and SPICE YouTube Channel

08 Jul 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Prof. Dr. Hiroshi Kawarada, School of Fundamental Science and Engineering, Waseda University, Japan With heavily boron doping (1022 cm-3 , ~6% ) diamond [1,2] exhibits type II superconducting with Tc offset>10K. Its high upper critical field which is estimated to be H2(0) = 11.5 T [3]. These diamonds are produced from gas phase such as CH4, CO2 with the addition of boron during plasma assisted chemical vapor deposition. Boron behaves as acceptor in diamond lattice as it does in Si and changes semiconducting diamond to metallic diamond in the degenerated semiconductor. We have demonstrated diamond superconducting quantum interference device (SQUID) has been demonstrated [4,5]. SQUID is a sensor for extremely small magnetic field used in material science, medical equipment, mineral exploration. In addition, it has also been used in qubit. Especially in Xmon qubit [6] which is a kind of transmon qubit [7] used for quantum computer. It is an important component enabling to tune qubit frequency. General problems with SQUID's materials are temperature change, natural oxidation, and deterioration due to collision. Hence, we have fabricated a highly robust SQUID Among such demonstrations, the SQUID composed of the trench-type or step-type Josephson junctions (JJs), which were formed in the boundary of discontinuous (111) sectors, operated at 10 K above liquid helium temperature (4.2 K) [5]. Unlike the previous structure included (001) surface (Tc < 4.2 K) [4], these trench or step-type JJs were composed of only (111) surface (Tc = 10K) [1,4]. At present Vp-p=47.7 μV at 1.6 K is the highest value in diamond SQUIDs. One of the unique properties of diamond is the close coexistence of superconductivity and two-dimensional Hall gas (2DHG) in a transistor structure [8]. 2DHG diamond field effect transistors (FETs) exhibit high power microwave operation [9]. All diamond Josephson (Jo) FET that exhibits gate control on the Josephson coupling ultimately leads to the realization of electrically tunable transmon qubits [10] (gatemon). [1] A. Kawano HK et al. Phys. Rev. B,82 (2010) 085318 [2] M.Watanabe, HK, Phys. Rev. B,85 (2012) 184516 [3] T. Kageura, HK et al., Diamond and Related Materials 90 (2018) 181. [4] T. Kageura, HK et al., Sci. Rep. 9, (2019) 15214 [5] A. Morishita, HK et al., Carbon 181, (2021) 379. [6] R. Barends, C. Neill et al., Phys. Rev. Lett. 111 (2013) 080502. [7] J. Koch, R.J. Schoelkopf et al., Phys. Rev A 76 (2007) 042319. [8] S. Imanishi HK et al. IEEE Elec. Dev. Lett. 42 (2021) 204. [9] S. Imanishi HK et al. IEEE Elec. Dev. Lett. 40 (2019) 279. [10] T..Larsen, C. M. Marcus et al. Phys. Rev. Lett. 115 (2015) 127001. at Zoom
09 Jul 2021

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau10:30 Uhr s.t., None
Thomas Kühne, Department of Chemistry, University of Padeborn

12 Jul 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., usually Staudingerweg 7, Minkowskiraum
Birte Sauer, Institut für Physik
at Zoom for now

### SFB/TR49/SFB TRR 173 Spin+X-Kolloquium/TopDyn - Seminar experimentelle Physik der kondensierten Materie

###### SFB/TR49 - Prof. Dr. Elmers16:00 Uhr s.t., None
Silvia Tacchi, Istituto Officina dei Materiali - IOM
at Zoom

13 Jul 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., None
 Nick Hutzler, Caltech, California Institute of Technology, USA The fact that the universe is made entirely out of matter, and contains no free anti-matter, has no physical explanation. The unknown process that created matter in the universe must violate a number of fundamental symmetries, including those that forbid the existence of certain electromagnetic moments of fundamental particles whose signatures are amplified by the large internal fields in polar molecules. We discuss spectroscopic and theoretical investigations into polyatomic molecules that uniquely combine multiple desirable features for precision measurement, such as high polarizability through symmetry-lowering mechanical motions, novel electronic and bonding structures, laser cooling, and exotic nuclei. at Zoom
14 Jul 2021

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:30 Uhr s.t., None
Friederike Schmid, Johannes Gutenberg University
at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Christian Pfleiderer, TU Munich
##### Topological protectorates of Fermi surfaces
at Zoom and SPICE YouTube Channel

15 Jul 2021

### Theoriekolloquium

###### Die Dozierenden der Theoretischen Physik16:00 Uhr s.t., Newton-Raum, Staudinger Weg 9, 01-122
 Francesco Piazza, MPIPKS - Dresden TBA Topic: Th. Kolloq. Time: Jul 15, 2021 04:00 PM Amsterdam, Berlin, Rome, Stockholm, Vienna Join Zoom Meeting https://zoom.us/j/94666378028?pwd=OThVejk4bHF6WkhQRU9LaWV2VWNzUT09 Meeting ID: 946 6637 8028 Passcode: 090910 at Zoom

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Prof. Dr. Stefan Filipp, Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften The rapid development of quantum technologies in the recent past has brought us a step closer to operational quantum computers that hold promise to outperform conventional computers in certain types of problems. While a large number of qubits is necessary to run complex algorithms, fast and high-fidelity gate operations of different types are as important. We utilize a system based on fixed-frequency superconducting qubits that are characterized by their stability, relatively long coherence times and scalability. On this platform we explore different ways to increase the performance of future quantum processors. We demonstrate that optimal control techniques allow us to shape microwave control pulses and realize fast single-qubit pulses without sacrificing their fidelity. Furthermore, we explore measurement techniques with a high duty cycle to overcome the challenge of time-consuming optimization sequences. For the generation of entangled two-qubit states we make use of a parametrically driven tunable coupler and implement different types of gates. Since exchange-type gates preserve the number of qubit excitations these are particularly well suited for quantum chemistry algorithms in which the number of electrons in the molecule is typically fixed. With this choice of gates we can make best use of the available hardware and realize short algorithms that finish within the coherence time of the system. With gate fidelities around 95% we compute the eigenstates within an accuracy of 50 mHartree on average, a good starting point for near-term applications with scientific and commercial relevance. at Zoom

### Emergent AI Center Seminars

###### JGU Research Center for Algorithmic Emergent Intelligence14:00 Uhr s.t., Online
 ADVAIT MADHAVAN, University of Maryland, National Institute of Standards and Technology TBA at Zoom
16 Jul 2021

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau10:30 Uhr s.t., None
Martin Hanke-Bourgeois, Department of Mathematics, JGU Mainz

21 Jul 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Shunsuke Fukami, Tohoku University
##### Electrical manipulation of non-collinear antiferromagnet
at Zoom and SPICE YouTube Channel

28 Jul 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Alexander Mook, University of Basel
##### Interacting and higher-order topological spin excitations
at Zoom and SPICE YouTube Channel

01 Sep 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Benedetta Flebus, Boston College
##### Magnetic topological phases in dissipative systems
at Zoom and SPICE YouTube Channel

08 Sep 2021

### Emergent AI Center Seminars

###### JGU Research Center for Algorithmic Emergent Intelligence12:00 Uhr s.t., Online
 Dr. Sara Vieira-Silva, Laboratory of Molecular Bacteriology (Rega Institute), KU Leuven, Belgium Sara Vieira-Silva's main research interests are the boundaries of the healthy human gut microbiota variation and the role of dysbiosis in disease, especially through the promotion of inflammation and production/degradation of bioactive compounds. She combines her background in microbial comparative genomics and evolutionary ecology, with hypothesis-driven experimental design. In close collaboration with clinical experts, she approaches quantitatively the contribution of host-associated microbial communities to pathophysiology, notably in the clinical context of inflammatory, metabolic and neuropsychiatric disorders. at Zoom
15 Sep 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Katja Nowack, Cornell University
##### Local magnetic measurements of quantum materials
at Zoom and SPICE YouTube Channel

22 Sep 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Jack Nathaniel Carter-Gartside, Imperial College London
##### Reconfigurable Training, Vortex Writing and Noise-Tolerant Reservoir Computation via Spin-Wave Fingerprinting in an Artificial Spin-Vortex Ice
at Zoom and SPICE YouTube Channel

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau10:00 Uhr s.t., None
Daniela Janka Bauer, Computer Science, JGU Mainz
at MS Teams

24 Sep 2021

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau10:30 Uhr s.t., None
Prof. Dr. David Landau, Center for Simulational Physics, The University of Georgia, Athens, GA, U.S.A.
at Zoom

28 Sep 2021

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau10:00 Uhr s.t., None
Yannick Witzky, Institut für Phisik
at Zoom

Masterkolloquium

29 Sep 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Stefano Bonetti, Stockholm University
##### Inertial spin dynamics in ferromagnets
at Zoom and SPICE YouTube Channel

### Theorie-Palaver

###### Institut für Physik15:30 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)
 Robert McGehee, Michigan U. In this talk, we estimate the maximum reasonable direct detection rate for sub-GeV dark matter scattering off nucleons and compare it to a plethora of experimental proposals' projected sensitivities. We then introduce a new class of HighlY interactive ParticlE Relics (HYPERs) which can actually have a nucleon scattering cross section as large as this maximum value. This is made possible by a late-time phase transition in the dark sector which decreases the mass of the mediator. HYPERs present a novel dark matter benchmark in an otherwise sparsely populated, but vigorously probed, parameter space.Slides here... at Zoom
13 Oct 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Markus Garst, KIT
##### Magnetic skyrmion strings: how they bend, twist and vibrate
at Zoom and SPICE YouTube Channel

19 Oct 2021

### Theorie-Palaver

###### Institut für Physik14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)
 Matthias Neubert, JGU Mainz Jet cross sections at high-energy colliders exhibit intricate patterns of logarithmically enhanced higher-order corrections. In particular, so-called non-global logarithms emerge from soft radiation emitted off energetic partons inside jets. While this is a single-logarithmic effect at lepton colliders, at hadron colliders phase factors in the amplitudes lead to double-logarithmic corrections starting at four-loop order. This effect was discovered a long time ago, but not much is known about the higher-order behavior of these terms and their process dependence. We derive, for the first time, the all-order structure of these "super-leading logarithms" for generic $$2\to l$$ scattering processes at hadron colliders and resum them in closed form.Slides here... at Zoom

### Physikalisches Kolloquium

###### Institut für KernphysikSonderseminar: 16 Uhr c.t., Staudinger-Hörsaal, Ackermannweg 10, MPI-P
 Kirill Melnikov, TTP, Karlsruher Institute of Technology To be announced Sonderseminar The location of the first colloquium is Staudinger-Hörsaal, Ackermannweg 10, MPI-P
20 Oct 2021

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau17:00 Uhr s.t., None
Thomas M Truskett,, Department of Chemical Engineering, The University of Texas at Austin
at Zoom

IRTG Lecture

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Achim Rosch, University of Cologne
##### Archimedean screw and time quasi-crystals in driven chiral magnets
at Zoom and SPICE YouTube Channel

### Theorie-Palaver

###### Institut für Physik15:00 Uhr s.t., Staudingerweg 7, 05-427
 Frank Saueressig, Nijmegen The asymptotic safety program strives for a high-energy completion of gravity and gravity-matter systems by an interacting renormalization group fixed point, the Reuter fixed point. The fixed point renders the theory safe from unphysical divergences at high energies and equips the construction with predictive power. In this talk I will give a pedagogical introduction to the program. In particular, I will argue that the inclusion of form factors - generalizing the running couplings encountered in quantum field theory to curved spacetime - is essential for investigating questions related to the causality and unitarity of Asymptotic Safety. Moreover, I will outline how form factors provide a concrete perspective for formulating various quantum gravity programs in a unifying language.
21 Oct 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Prof. Tanya Zelevinsky, Columbia University Techniques for controlling quantum states of atoms have led to extremely precise metrology and studies of degenerate gases.  Extending such techniques to various types of molecules further enriches the understanding of fundamental physics, basic chemical processes, and many-body science.  Samples of diatomic molecules can be created by binding laser-cooled atoms, or by direct molecular laser cooling.  We explore both approaches and demonstrate high-precision metrology with an optical-lattice based molecular clock, as well as photo-chemistry in the highly nonclassical domain. at Zoom
25 Oct 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., Staudingerweg 7, Minkowskiraum
Johann Martyn, Institut für Physik
##### Directional measurement of sub-MeV solar neutrinos in Borexino
at Zoom also available

26 Oct 2021

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)
 Peera Simakachorn, DESY and U. Hamburg In presence of a kination era, induced by a fast-moving scalar field dominating the energy density of the universe, stochastic gravitational-wave (GW) backgrounds can be dramatically enhanced. Not only this could boost the detectability of primordial GW from cosmic strings or primordial inflation at current and future-planned GW observatories, but it could also help constraining particle theories that generate the kination phase. We find that kination era at the GeV-EeV scale can induce a GW peak in the window of ET and CE. In this work, we present two classes of spinning axion models in which a phase of matter-domination followed by kination-domination is naturally generated. Ultimately, it is possible to relate the GW signatures to the relic abundance of axion dark matter or to the baryon asymmetry of the universe.Slides here... at Zoom

### Physikalisches Kolloquium

###### Institut für Kernphysik16 Uhr c.t., Hörsaal CO2 Chemie - Nord-Ost (2321) Duesbergweg 10 - 14
 Alfons Weber, University of Mainz Neutrinos are the most abandon matter particle in the universe, but very little is known about them. Originally proposed by Pauli as an undetectable placeholder to save energy- and angular momentum conservation, they have come a long way and surprising us at every step. It is now known, that neutrinos have mass and that the mass- and interaction-eigenstates are not the same, which leads to a phenomenon called neutrino oscillations. The colloquium will report on the current knowledge on the field concentrating on accelerator based experiments and highlight future facilities, which will make precision experiments and might tell us, if neutrinos and anti-neutrinos behave the same or not. Differences between neutrinos and anti-neutrinos (CP-violation) may shed some light why our universe is matter dominated.
27 Oct 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Kirsten von Bergmann, Hamburg University
##### Nano-scale skyrmions and atomic-scale spin textures studied with STM
at Zoom and SPICE YouTube Channel

28 Oct 2021

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:15 Uhr s.t., None
 Katrin Amann-Winkel, JGU, Physics Water is the most important liquid for life on earth. However, many properties of water are most anomalous, such as the density maximum at 4°C or the divergence of the heat capacity upon cooling. Although the water molecule is seemingly simple, the hydrogen-bonded network keeping these molecules together and determining the many anomalous macroscopic properties of water, is still a puzzle. Computer-simulations suggest, that the anomalous behaviour of ambient and supercooled water could be explained by a two state model of water. The hypothetical existence of two distinct liquid states, namely high- and low-density liquid (HDL, LDL), is considered controversial. An important role in this ongoing debate plays the amorphous solid states of water. Since the discovery of two distinct amorphous ices with different density (high- and low density amorphous ice, HDA and LDA) it has been discussed whether and how this phenomenon of polyamorphism at high pressures and low temperatures is connected to the occurrence of two distinct liquid phases (HDL and LDL). X-ray scattering experiments on both supercooled water and amorphous ice are of major importance for our understanding of water. In my talk I will give an overview on our recent experimental findings on amorphous ice and supercooled water. at Zoom

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Prof. Ilja Gerhardt, Leibniz Universität Hannover The past decade has seen a resurrection of experiments with hot atomic vapors. Their physics covers atomic clocks, magnetic and electric sensing and optical devices. In parallel the field of quantum technology develops ever better single photon sources and quantum sensing devices at the nano-scale. Our own efforts of combining both techniques started with single photon slow light experiments. [1,2]. They evolved towards the optimization of Faraday filters [3,4,5], and took the baby-steps towards storing a single photon into hot atomic vapor with Rydberg transitions [6]. With the technology at hand, we further aimed for the combination of solid-state samples with atomic vapors. This can be envisioned in a sensing setting [7] – but also other coupling schemes can be envisioned. In this talk I will review the prospects and challenges for combining single photon sources with hot atomic vapors. The valuable tool of atomic filtering and its combination with quantum optics will be explained and reviewed. References [1] Molecular photons interfaced with alkali atoms Petr Siyushev, Guilherme Stein, Jörg Wrachtrup, Ilja Gerhardt Nature, 2014, 509, 66-70 [2] Two-photon interference in an atom-quantum dot hybrid system Hüseyin Vural, Simone L. Portalupi, Julian Maisch, Simon Kern, Jonas H. Weber, Michael Jetter, Jörg Wrachtrup, Robert Löw, Ilja Gerhardt, Peter Michler Optica, 2018, 5, 367-373 [3] Na-Faraday rotation filtering: The optimal point Wilhelm Kiefer, Robert Löw, Jörg Wrachtrup, Ilja Gerhardt Scientific Reports, 2014, 4, 6552 [4] Simultaneous Faraday filtering of the Mollow triplet sidebands with the Cs-D1 clock transition Simone Luca Portalupi, Matthias Widmann, Cornelius Nawrath, Michael Jetter, Peter Michler, Jörg Wrachtrup, Ilja Gerhardt Nature Communications, 2016, 7, 13632 [5] How anomalous is my Faraday filter? Ilja Gerhardt Optics Letters, 2018, 43, 5295-5298 [6] Two Step Excitation in Hot Atomic Sodium Vapor Bernd Docters, Jörg Wrachtrup, Ilja Gerhardt Scientific Reports, 2017, 11760 [7] A Rubidium Mx-magnetometer for Measurements on Solid State Spins Daniel Arnold, Steven Siegel, Emily Grisanti, Jörg Wrachtrup, Ilja Gerhardt Review of Scientific Instruments, 2017, 88, 023103 at Zoom
02 Nov 2021

### Theorie-Palaver

###### Institut für Physik14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)
 Miguel Escudero, TUM We are living exciting times in Cosmology and we may be at the edge of a shift in the cosmological paradigm. At present, there is a 4-5 sigma tension in the value of the Hubble constant between the value that is inferred locally (from Cepheids and type Ia Supernovae) and the value predicted in LCDM. This tension has been growing for the past 6-7 years and many models have been proposed to account for it. In the first part of this seminar, I will review the status of the Hubble tension. I will discuss the observational situation and review the main theoretical approaches developed to account for it. In the second part of the talk, I will focus on my contribution to the topic (see 1909.04044, 2004.01470, 2103.03249). I will show that the Hubble tension can be substantially ameliorated in the presence of an eV-scale pseudo-Goldstone boson that interacts with neutrinos: the Majoron. This particle is directly related to the neutrino mass mechanism and naturally arises in the context of the type-I seesaw mechanism with a spontaneously broken global U(1)L symmetry. Remarkably, I will further show that in some regions of the parameter space, this scenario could also account for the observed baryon asymmetry of the Universe via sterile neutrino oscillations in the early Universe. Thus, providing an intriguing link between low-scale leptogenesis, neutrino mass generation and the Hubble tension.Slides here... at Zoom

### Physikalisches Kolloquium

###### Institut für Kernphysik16 Uhr c.t., None
 Dr. Mickaël Rigault, CNRS/IN2P3 Type Ia Supernovae are powerful distance indicators that enable us to measure the recent expansion rate of the Universe and thereby derive the properties of dark energy. They are also key to directly measure the Hubble Constant H0, found to be incompatible with predictions based on the standard model of cosmology anchored by Cosmic Microwave Background data. Yet, despite 20 years of success, we still largely ignore the underlying mechanism responsible for the astrophysical event a Type Ia Supernovae is. This is now limiting further progress on measuring cosmological parameters and questions the accuracy of our measurements that now entire the era of high precision. In this presentation, I will introduce the derivation of cosmological parameters with Type Ia Supernovae (dark energy’s w and H0) and how the study of the correlation between Supernova's properties that of their hosts gives us critical information to improve their use as cosmological probes. I will finish by introducing the ongoing Zwicky Transient Facility survey that is new revolutionising the field and opening new area for SN Cosmology.Slides here... at Zoom
03 Nov 2021

### PRISMA+ Colloquium

###### Institut für Physik16:00 Uhr s.t., None
 Natalie Klco, Caltech please note different time! at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Peter Oppeneer, Uppsala University
##### Analytic and ab initio theory of magnetization dynamics
at Zoom and SPICE YouTube Channel

04 Nov 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Prof. Cornelia Denz, Universität Münster Within the last decades, customized light fields have proven their significance in various research areas, ranging from nano-scale complexity over optical micromanipulation to high-resolution imaging and material machining. Besides well-established amplitude and phase modulation, within recent years, structured light incorporated orbital and spin angular momentum. Moreover, polarization has been rediscovered as a degree of freedom that enriches the diversity of spatially structured light. In our contribution, we discuss creating 3d light landscapes by interfering counterpropagating beams or by tightly focusing polarization structured light. In this way, spatial entanglement of spin- and orbital angular momentum is created, leading to the observation of entanglement beating. Moreover, non-negligible longitudinal vector field components appear in focal light landscapes forming exotic singular and topological structures as arrays of Möbius strips or skyrmionics Hopfions. We evince the benefit of these fields for advanced optical trapping and information processing. at Zoom

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau9:00 Uhr s.t., None
Janka Bauer, Institute of Physics, Johannes-Gutenberg University Mainz
at Teams

Masterkolloquium

09 Nov 2021

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)
 Joan Ruiz, IFIC, Valencia U. - CSIC Recent experimental results on the B-anomalies, CP-violation in charm, or the muon (g-2) hint at new physics models where the additional interactions are specific to the quark and lepton families. In this context, searches for the electric dipole moment (EDM) of heavy-flavored baryons are especially motivated. Using bent crystal technology and the highly energetic beams of the LHC, the EDM of very short-lived particles can be measured for the first time (1612.06769, 2010.11902, 2110.00845). In addition, the direct determination of the tau (g-2) is possible with this novel experimental method (1901.04003). The different aspects of the measurement will be summarized along with the expected sensitivities. From a more phenomenological perspective, we will also see what are the effective operators contributing to the baryon EDM and what is their expected size. In particular, new limits on the charm and bottom quark EDM are derived from already existing measurements (1905.02513). We will analyze the implications of these bounds for new physics models, comparing them against other competing observables.Slides here... at Zoom

### Physikalisches Kolloquium

###### Institut für Kernphysik16 Uhr c.t., Hörsaal CO2 Chemie - Nord-Ost (2321) Duesbergweg 10 - 14
 Christian Smorra, University of Mainz Precision tests of CPT invariance – one of the fundamental symmetries in the Standard Model – include high-precision comparisons of the charge-to-mass ratios and the magnetic moments of the proton and antiproton. The ERC project STEP aims to improve these measurements by developing transportable antiproton traps to eliminate the limitations imposed by the magnetic field fluctuations of the antiproton decelerator of CERN. Further, we target the development of more precise spectroscopy methods for the antiproton charge-to-mass ratio and the magnetic moment. To this end, we have developed a sympathetic cooling method based on coupled harmonic oscillators that allows to couple a single proton to a cloud of laser-cooled beryllium ions. Recently, we succeeded in cooling the proton to 15% of the environment temperature using an LC circuit to enhance the coupling strength to the beryllium ions [1]. The cooling method is applicable to a broad range of trapped particles independent of the charge, and can be applied also to antiprotons, highly-charged or molecular ions. We further discuss the prospects of decreasing the temperature down to the 10 mK level in presence of the heating from the LC circuit and frequency uncertainties and drifts. A further decrease in temperature would greatly reduce the uncertainty of proton/antiproton magnetic moment measurements, and improve tests of CPT invariance in the baryon sector, and searches for dark matter particles, such as axions [2, 3] or millicharged particles [4]. [1] M. Bohman et al., Nature 596, pages 514–518 (2021). [2] C. Smorra et al., Nature 575, pages 310–314 (2019). [3] J. A. Devlin et al., Phys. Rev. Lett. 126, 041301 (2021). [4] D. Budker et al., arXiv:2108.05283 [hep-ph] (2021).Slides here...
10 Nov 2021

### Theorie-Palaver

###### Institut für Physik15:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)
 Kevin Falls, SISSA In this talk I will present a novel scheme for the exact renormalisation group motivated by the desire of reducing the complexity of practical computations. The key idea is to specify renormalisation conditions for all inessential couplings, leaving us with the task of computing only the flow of the essential ones. To achieve this, a renormalisation group equation for the effective average action which incorporates general non-linear field reparameterisations is utilised. The field reparameterisations allow one to fix the values of inessential couplings. The scheme has been used to investigate the Wilson-Fisher fixed point in the three dimensional Ising model and the Reuter fixed point in quantum gravity. I will discuss the results of these investigations and the implications for quantum gravity. at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Tomas Jungwirth, Institute of Physics of the Science Academy of the Czech Republic
##### Altermagnetism: spin-momentum locked phase protected by non-relativistic symmetries
at Zoom and SPICE YouTube Channel

11 Nov 2021

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:15 Uhr s.t., None
 Syuji Fujii, Osaka Institute of Technology, Japan Over the past decade or so, there has been increasing interest in the adsorption of colloidal particles at the air/water, oil/water and solid/water interfaces. This emerging field has led to new concepts and materials in soft dispersed systems such as “colloidosomes”, “armored bubbles”, “dry water” and “liquid marbles”, with potential applications being suggested in microencapsulation and biotechnology. The soft dispersed systems stabilized with inorganic particles (e.g. silica, alumina and graphene) have been mainly studied for a long time, and recently those stabilized with organic particles, including synthetic polymer particles, start to gain interest. Here, I will give a talk on our research related to liquid marbles (dry liquids) that are stabilized by polymer particles. The polymer particles have been demonstrated to be particularly attractive as the stabilizer for the soft dispersed systems, because they can be readily designed with specific surface chemistries using various functional monomers and by post surface modifications. Successful particle synthesis would inspire the construction of well-defined and functionalized particle-stabilized liquid marble systems. In this talk, liquid marbles (water-in-air dispersed system) stabilized solely with polymer particles will be presented in detail. The stabilities, microstructures and movements of these dispersed systems can be controlled by external stimuli: liquid marbles can be disrupted and/or move on demand. About the speaker: Prof. Syuji Fujii graduated from Kobe University (Ph.D. 2003). His postdoctoral studies were carried out at University of Sussex (UK) from 2003 to 2004 and at University of Sheffield (UK) from 2004 to 2006. He joined Osaka Institute of Technology as a Lecturer in 2006 and was promoted to Associate Professor in 2013 and Professor in 2017. His major research interests focus on synthetic polymer chemistry, design and characterization of polymer-based particles, biomimetics, and particle-stabilized soft dispersed systems including emulsions, foams, liquid marbles and dry liquids. at Zoom

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Prof. Christine Silberhorn, Universität Paderborn Quantum technologies promise a change of paradigm for many fields of application, for example in communication systems, in high-performance computing and simulation ofquantum systems, as well as in sensor technology. They can shift the boundaries of today’ssystems and devices beyond classical limits and seemingly fundamental limitations. Photonicsystems, which comprise multiple optical modes as well as many nonclassical light quantum states of light, have been investigated intensively in various theoretical proposals over the last decades. However, their implementation requires advanced setups of high complexity, which poses a considerable challenge on the experimental side. The successful realization of controlled quantum network structures is key for many applications in quantum optics and quantum information science. Here we present three differing approaches to overcome current limitations for the experimentalimplementation of multi-dimensional quantum networks: non-linear integrated quantum optics, pulsed temporal modes and time-multiplexing. Non-linear integrated quantum devices with multiple channels enable the combinations of different functionalities, such as sources and fast electro-optic modulations, on a single compact monolithic structure. Pulsed photon temporalmodes are defined as field orthogonal superposition states, which span a high dimensional system. They occupy only a single spatial mode and thus they can be efficiently used in singlemode fibre communication networks. Finally, time-multiplexed quantum walks are a versatile tool for the implementation of a highly flexible simulation platform with dynamic control of the underlying graph structures and propagation properties. at Zoom
15 Nov 2021

### SFB/TR49/SFB TRR 173 Spin+X-Kolloquium/TopDyn - Seminar experimentelle Physik der kondensierten Materie

###### SFB/TR49 - Prof. Dr. Elmers16:00 Uhr s.t., TUK 46/HS 270 and on-line
Philipp Gegenwart, Augsburg University
at Zoom

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., Staudingerweg 7, Minkowskiraum
Florian Thomas, Institut für Physik
##### A fast model for CRES signals in Project 8
at Zoom also available

16 Nov 2021

### Theorie-Palaver

###### Institut für Physik14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)
 Jeff Dror, UC, Santa Cruz Existing searches for cosmic axions relics have relied heavily on the axion being non-relativistic and making up dark matter. However, light axions can be copiously produced in the early Universe and remain relativistic today, thereby constituting a Cosmic axion Background (CaB). In this talk I will study the production and detection of a CaB. Prototypical examples of axion sources are thermal production, dark-matter decay, parametric resonance, and topological defect decay. Each of these has a characteristic frequency spectrum that can be searched for in axion direct detection experiments. I will focus on the axion-photon coupling and study the sensitivity of current and future versions of ADMX, HAYSTAC, DMRadio, and ABRACADABRA to a CaB, finding that the data collected in search of dark matter can be repurposed to detect axion energy densities well below limits set by measurements of the energy budget of the Universe. In this way, direct detection of relativistic relics offers a powerful new opportunity to learn about the early Universe and, potentially, discover the axion. at Zoom

### Physikalisches Kolloquium

###### Institut für Kernphysik16 Uhr c.t., None
 Hartmut Löwen, Universität Düsseldorf Ordinary materials are "passive" in the sense that their constituents are typically made by inert particles which are subjected to thermal fluctuations, internal interactions and external fields but do not move on their own. Living systems, like schools of fish, swarms of birds, pedestrians and swimming microbes are called "active matter" since they are composed of self-propelled constituents. Active matter is intrinsically in nonequilibrium and exhibits a plethora of novel phenomena as revealed by a recent combined effort of statistical theory, computer simulation and real-space experiments. After an introduction into the physics of active matter focussing on biological and artificial microswimmers as key examples of active soft matter [1], a number of single-particle and collective phenomena in active matter will be adressed including novel structures like "rotelles" [2] and "active droploids" [3]. [1] For a review, see: C. Bechinger, R. di Leonardo, H. Löwen, C. Reichhardt, G. Volpe, G. Volpe, Active particles in complex and crowded environments, Reviews of Modern Physics 88, 045006 (2016). [2] C. Scholz, A. Ldov, T. Pöschel, M. Engel, H. Löwen, Surfactants and rotelles in active chiral fluids, Science Advances 7, eabf8998 (2021). [3] J. Grauer et al, Active droploids, arXiv:2109.10677Slides here... at Recording of the presentation
17 Nov 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Hidekazu Kurebayashi, University College London
##### Magnetism and spin dynamics control by carrier doping in van der Waals magnet Cr2Ge2Te6
at Zoom and SPICE YouTube Channel

### PRISMA+ Colloquium

###### Institut für Physik13:00 Uhr s.t., IMB Auditorium (Ackermannweg 4 · 55128 Mainz ) and
 Adi Ashkenazi, University Tel Aviv please not that this is a hybrid format: it takes place at IMB auditorium an is streamed via Zoom at Zoom
18 Nov 2021

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau10:30 Uhr s.t., None
Emma Rossi, University of Padua, Italy
at Zoom

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Prof. Morgan Mitchell, The Institute of Photonic Sciences In 1981, a newly-minted PhD named Carlton Caves proposed to use squeezed light'’ to beat the shot noise limit, and thereby improve the sensitivity of gravitational wave detectors. Thirty years later, the GEO600 gravitational wave detector demonstrated improved sensitivity using squeezed light. Today, forty years after his proposal, Caves is a Professor Emeritus, and gravitational waves are routinely detected with the help of squeezed light. Meanwhile, in 1993, the squeezing of atomic spins was proposed as a way to improve the sensitivity of atomic clocks, magnetometers, gravimeters, and so forth. If these atomic instruments proceed along the same time-line as gravitational-wave detectors, we should expect to see the first real-world use of squeezing in atomic instruments in the next few years. In this talk, I will describe some of the progress in this direction, including the use of squeezed light and squeezed spins in magnetometry. I will try to explain how quantum noise in a magnetometer is, and is not, like quantum noise in a gravitational wave detector, and some unexpected features that make magnetometers particularly well-suited for spin squeezing. If time permits, I will say something about the potential to use squeezing in optical lattice clocks, to improve the stability of our best time-keeping instruments. at Zoom
22 Nov 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., only at Zoom
Renjie Wang, Institut für Physik

23 Nov 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16 Uhr c.t., None
 Rainer Blatt, Innsbruck In this talk, the basic functional principles of quantum information processing are reviewed and the state-of-the-art of the Innsbruck trapped-ion quantum computer is reported. With strings of trapped ions, we implement a quantum information processor and perform quantum operations. We present an overview on the available quantum toolbox and discuss the scalability of the approach. The quantum way of doing computations is illustrated with analog and digital quantum simulations. Employing universal quantum computations, we investigate the dynamics of the Lattice Schwinger model [1], a gauge theory of 1D quantum electrodynamics and using a hybridclassical ansatz, we determine steady-state properties of the Hamiltonian [2]. Using tailored quantum operations, we obtain optimized measurements for spectroscopy [3]. [1] E. A. Martinez et al., Nature 534, 516 (2016). [2] C. Kokail et al., Nature 569, 355–360 (2019). [3] C. Marciniak et al., arXiv:2106.01860 (2021). at Slides

### Theorie-Palaver

###### Institut für Physik14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)
 Guilherme Guedes, U. Granada and LIP In this talk, I will discuss the calculation of the renormalization group equations (RGEs) of theories extending the Standard Model effective field theory (SMEFT) with higher-dimensional operators or with a new degree of freedom. In the first case, I will explore the running of bosonic dimension-eight operators triggered by two dimension-six interactions. In the second scenario I will consider extending the SMEFT to include an axion-like particle and study the RGE effects up to dimension 5. In both cases, some phenomenological consequences will be discussed.Slides here... at Zoom
24 Nov 2021

### SPICE-Spin+X Seminar

Hariom Jani, NUS
##### Antiferromagnetic Skyrmionics: generating and controlling topological textures
at Zoom and SPICE YouTube Channel

### PRISMA+ Colloquium

###### Institut für Physik13:00 Uhr s.t., None
Martin Hoferichter, Universität Bern
at Zoom

25 Nov 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Dr. Sarah Skoff, Technische Universität Wien Since quantum technology is becoming advanced, new ways are sought to make miniature systems for quantum networks and sensing. Solid-state quantum emitters have therefore moved into focus as they lend themselves for integration into nanophotonic platforms and come in a variety of forms and with a variety of different level structures. Here, I want to present two different kinds of solid-state platforms, single molecules in solids and quantum emitters in 2D materials. I will present measurements on coupling these quantum emitters to waveguides, in particular optical nanofibers. These are waveguides that are naturally integrated with optical fibers and enhance the light-matter interaction by their strong transverse confinement of the guided light field. I will also show how the light-matter interaction can be further increased by employing fiber-based cavities. These cavities have been shown to work equally well at room temperature and cryogenic temperatures, where the latter is still most often a requirement for solid-state system due to the phonons from the host material. However due to the 2D nature of the host material, quantum emitters in 2D hexagonal Boron nitride may provide a platform for quantum tech-nology that could also operate a room temperature and I will give an overview of recent measurements with these emitters and give an outlook of our endeavour to bring solid-state quantum optics to a room temperature environment. at Zoom

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:15 Uhr s.t., Newton room
 Maximilian Hielscher, JGU, Chemistry The optimization of electro-organic reactions poses a challenge due to the various parameters involved. Quite often those parameters are not independent from each other, leading the experimental scientist using linear approaches into an optimization loophole. I report a strategy for the optimization of the anodic oxidative dehydrogenative C,C cross-coupling reactions for the synthesis of biphenols and biaryles based on Design of Experiments (DoE), which overcomes the drawbacks of linear optimization approaches. These strategies are demonstrated on the optimization of electrochemical flow, as well as batch processes, but are universally applicable to (multi)-target optimization.

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:45 Uhr s.t., Newton room
 Torsten Linder, JGU, Chemistry Though the basis of microfluidics is simple, the creation of microgels via microfluidics faces various challenges. I report different working experimental setups for the creation of micro hydrogel particles as well as analytics of the swelling kinetics of the obtained micro-hydrogels. Furthermore, the challenges of creating core-shell microparticles, with temperature-sensitive cores and temperature-insensitive shells and possible solutions will be presented.
29 Nov 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., only at Zoom
Jakub Kremer, Institut für Physik

30 Nov 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16 Uhr c.t., None
 Achim Schwenk, Technische Universität Darmstadt The strong interaction described by quantum chromodynamics gives rise to the formation of hadrons and nuclei that constitute the baryonic matter in the Universe and governs the densest matter in neutron stars and highest temperatures reached in compact object mergers. Combined with the electroweak interaction, it determines the structure and properties of all nuclei in the nuclear chart in a similar way as quantum electrodynamics shapes the periodic table of elements. However, big science problems of the strong interaction remain unsolved, especially regarding the structure of extreme neutron-rich matter in the laboratory and stars. New facilities for rare isotopes will discover over a thousand new isotopes, getting as close as possible to the nuclei in the Universe's heavy-element nucleosynthesis pathway. On the theoretical side, there are impressive advances towards a unified description of all nuclei and matter based on effective field theories of the strong interaction combined with powerful many-body methods. In this colloquium, we will discuss the advances, status and challenges in strongly interacting matter, with a focus on how the nuclear chart emerges from nuclear forces and on the physics of neutron stars and neutron star mergers.Slides here... at Recording of the presentation

### Theorie-Palaver

###### Institut für Physik14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)
 Abhishek Banerjee, Weizmann Institute of Science The relaxion mechanism, which was proposed recently, can address the hierarchy problem without resorting to new physics at the TeV scale. Our prior efforts on this subject have produced several new results, which have interesting phenomenological implications. We have shown that the relaxion can account for the observed dark matter relic density and can be probed in various different frontiers. The relaxion has scalar coupling to the SM and as a result of the oscillating DM background, the fundamental constants of natures are oscillating in time as well. In this talk, I will discuss how the relaxion could be a viable DM candidate and then will discuss how to search for scalar DM (relaxion) using precision spectroscopy.Slides here... at Zoom
01 Dec 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Stéphane Mangin, CNRS
##### Spin-transport Mediated Single-shot All-optical Magnetization Switching of Metallic Films
at Zoom and SPICE YouTube Channel

02 Dec 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Dr. Romana Schirhagl, Groningen University Medical Center, Netherlands Free radicals play a key role in many biological processes including cell communication, immune responses, metabolism or cell development. But they are also involved whenever something is wrong in a cell and are thus important in many diseases including cardiovascular diseases, cancer or bacterial and viral infection. Unfortunately, they are very reactive and short lived and thus difficult to detect for the state of the art. We have used diamond magnetometry to achieve this. We make use of nanodiamonds which we bring into cells. We then use of NV centers in diamonds to perform relaxometry measurements. These are sensitive to spin noise (in this case from radicals) and deliver signals that are equivalent to T1 in conventional MRI but from nanoscale voxels. Using this method, we are able to quantify free radical generation with nanoscale resolution in the nanomole range (1). In our recent work we were able to detect free radical generation in single mitochondria (the energy factories of the cell) in isolated form as well as in their cellular environment (2). 1 Perona Martínez, F., Nusantara, A.C., Chipaux, M., Padamati, S.K. and Schirhagl, R., 2020. Nanodiamond Relaxometry-Based Detection of Free-Radical Species When Produced in Chemical Reactions in Biologically Relevant Conditions. ACS Sensors. 2 Nie, L., Nusantara, A.C., Damle, V.G., Sharmin, R., Evans, E.P.P., Hemelaar, S.R., van der Laan, K.J., Li, R., Martinez, F.P., Vedelaar, T. and Chipaux, M., Schirhagl, R., 2021. Quantum monitoring of cellular metabolic activities in single mitochondria. Science Advances, 7(21), p.eabf0573. at Zoom
06 Dec 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., only at Zoom
Moritz Hesping, Institut für Physik

07 Dec 2021

### Theorie-Palaver

###### Institut für Physik14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)
 Eran Palti, Ben-Gurion University of the Negev In this talk, I will introduce a particular formulation of the Weak Gravity Conjecture in AdS space in terms of the self-binding energy of a particle. The holographic CFT dual of this formulation corresponds to a certain convex-like structure for operators charged under continuous global symmetries. Motivated by this, we propose a conjecture that this convexity is a general property of all CFTs, not just those with weakly-curved gravitational duals. It is possible to test this in simple CFTs, the conjecture passes all the tests performed so far. at Zoom

### Physikalisches Kolloquium

###### Institut für Kernphysik16 Uhr c.t., None
 Edda Gschwendtner, CERN The construction of ever larger and costlier accelerator facilities has its limits, and new technologies will be needed topush the energy fronTer. Plasma wakefield acceleraTon is a rapidly developing field which appears to be a auspiciouscandidate technology for future high-energy acceleratorsproviding acceleraTon gradients a factor 10 to 1000 larger thanin convenTonal radio-frequency metallic caviTes used in current accelerators.This presentation introduces the plasma wakefield acceleration technology, shows the technological challenges, gives anoverview of the state of the art and shows promising results on the example of the advanced proton driven plasmawakefield experiment, AWAKE, at CERN.Slides here... at Recording of the presentation
08 Dec 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Gisela Schütz, MPI for Intelligent Systems
##### X-ray magnetization movies: Spin dynamics in reality
at Zoom and SPICE YouTube Channel

### PRISMA+ Colloquium

###### Institut für Physik13:00 Uhr s.t., None
Andreas Knecht, PSI
at Zoom

### Seminar über Theorie der kondensierten Materie / TRR146 Seminar

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau17:00 Uhr s.t., Galilei room, 01-128, Staudingerweg 9
Benjamin Trefz, Südzucker
at Zoom

09 Dec 2021

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:15 Uhr s.t., None
 Karen Johnston, University of Strathclyde, Glasgow Interfaces between different materials are ubiquitous in natural systems and in technological applications. Often, the interface gives rise to interesting phenomena that significantly affects the behaviour of the system. I will present studies of the interfacial behaviour in two types of system: a) polymer composites and b) heterogeneous nucleation. Polymer composites are typically comprised of filler particles, such as carbon fibres, or inorganic nanoparticles, embedded in a polymer matrix. Filler particles are added to alter the polymer properties, for example, to create lightweight and high strength composites that are widely used in the aerospace and automotive industries. The interfaces between the polymer and filler particles, determine the overall properties of the composite material. Simulations can provide molecular level insight into the interfacial structure and properties, which is extremely challenging to measure experimentally. I will show how simulations have provided insight into the properties of polymers at a solid interface [1-3]. Crystal nucleation from solution is known to mainly occur at interfaces (heterogeneous nucleation), although the mechanisms are not well understood. Experiments on glycine aqueous solutions found that oil and PTFE interfaces dramatically accelerates glycine nucleation compared to an air–-solution interface [4,5]. Molecular dynamics simulations found significantly enhanced vs depleted glycine concentrations at the oil-solution vs air-solution interfaces, respectively, which explains the observed nucleation behaviour [5]. [1] K. Johnston and V. Harmandaris, Soft Matter 8, 6320 (2012) [2] K. Johnston and V. Harmandaris, Macromolecules 46, 5741 (2013) [3] D. McKechnie et al. Polymer 195, 122433 (2020) [4] M. J. Vesga et al. Cryst. Eng. Comm. 21 2234 (2019) [5] D. McKechnie et al. J. Phys. Chem. Lett. 11, 2263-2271 (2020) at Zoom

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Prof. Gerhard Rempe, Max-Planck-Institut für Quantenoptik; TUM Quantum networks with long-lived memory devices are a promising platform for modular quantum computing and long-distance quantum communication. Using selected examples, the talk will discuss the state of the art achieved with single emitters in optical resonators for distributed quantum logic and secure quantum repeaters. at Zoom

### Theoriekolloquium

###### Die Dozierenden der Theoretischen Physik16:15 Uhr s.t., Zoom
 G. Semeghini, R. Verresen, Harvard University Zoom coordinates: https://uni-frankfurt.zoom.us/j/95275049840?pwd=TlJBL1g1dGVEVXF1eEhKOHh5bjV4QT09 Meeting-ID: 952 7504 9840 Kenncode: 297559 at Zoom
10 Dec 2021

at Zoom

13 Dec 2021

### Seminar about Experimental Particle and Astroparticle Physics (ETAP)

###### Institut für Physik12:30 Uhr s.t., only at Zoom
Frank Steeg, Institut für Physik

### SFB/TR49/SFB TRR 173 Spin+X-Kolloquium/TopDyn - Seminar experimentelle Physik der kondensierten Materie

###### SFB/TR49 - Prof. Dr. Elmers16:00 Uhr s.t., Kaiserslautern 46/HS 270
Heiko Wende, University of Duisburg-Essen
at Zoom

14 Dec 2021

### Physikalisches Kolloquium

###### Institut für Kernphysik16 Uhr c.t., None
 Dr. Benjamin Dönigus, Goethe-Universität Frankfurt The high collision energies reached at the Large Hadron Collider (LHC) at CERN lead to significant production rates of fragile objects, i.e. objects whose binding energies are small compared to the average kinetic energy of the particles produced in the system. Such objects are, for instance, light (anti-)nuclei and (anti-)hypernuclei. The most extreme example here is the hypertriton, a bound state of a proton, a neutron and a lambda, where the separation energy of the lambda is only around 130 keV. These states, from the anti-deuteron up to the anti-alpha nuclei, are nevertheless created and observed in the hot + rough environment of proton-proton and heavy-ion collisions at the LHC. The reached temperaturesarehigher than156 MeV, corresponding to 1.8 x1012K.Selected highlights ofmeasurements of these fragile objects will be presented.Slides here... at Recording of the presentation
15 Dec 2021

### PRISMA+ Colloquium

###### Institut für Physik13:00 Uhr s.t., None
Patrick Owen, Universität Zürich
at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t., None
Bert Koopmans, Eindhoven University of Technology
##### Femto-magnetism meets spintronics: Towards integrated magneto-photonics
at Zoom and SPICE YouTube Channel

16 Dec 2021

### Seminar über Quanten-, Atom- und Neutronenphysik (QUANTUM)

###### Institut für Physik14:00 Uhr s.t., None
 Prof. Irina Novikova, College of William & Mary, Williamsburg, Virginia/USA For some light-sensitive substances it is crucial to be able to measure their optical properties with minimal light exposure. At the same time, low-light imaging is technically challenging due to the dark noise of a CCD camera. In this talk I will describe a new imaging techniques that relies on quantum fluctuation analysis to image opaque objects at low-photon environment. We demonstrate that both squeezed vacuum and thermal vacuum can be effectively used for this purpose. At the same time, we successfully eliminate the camera dark noise problems by realizing a camera-based homodyne detection. at Zoom