Semesterübersicht Wintersemester 2023/2024

Sommersemester 2023 - Wintersemester 2023/2024 - Sommersemester 2024

04 Oct 2023

Seminar über die Physik der kondensierten Materie (SFB/TRR173 Spin+X und SFB/TR288 Kolloquium, TopDyn-Seminar)

JGU

13:00 Uhr s.t., tba.

Paul J. Kelly, University of Twente
Phenomenological theories in spintronics are usually based upon semiclassical formulations of transport like the Boltzmann or diffusion equations that cannot easily accommodate the fundamentally quantum character of energy bands and Fermi surfaces; this is more readily done using scattering theory. The challenge for first-principles scattering theory is to describe the diffusive regime in which most experiments are performed. I sketch the developments that have allowed us to realize this goal culminating in the extraction of charge and spin currents [1] from large scale relativistic scattering calculations [2] that include temperature-induced lattice and spin disorder [3]. I illustrate our approach with a study of the temperature dependence of the spin-flip diffusion length and spin Hall angle for the bulk 5d transition metals [4]. It allowed us to evaluate the transport parameters required to describe a spin current through interfaces between two non-magnetic metals or between a non-magnetic and a ferromagnetic metal and focus on the temperature dependence of the spin memory loss that describes interface spin flipping [5]. When we use it to study the spin Hall effect in a thin Pt film, we find that we cannot recover the bulk spin-flip diffusion length without taking surface effects into account. The same approach allows us to examine the shunting of a charge current passed through a bilayer parallel to the interface [1], the Fuchs-Sondheimer suppression of charge currents by surfaces and interfaces [1] or the efficiency with which a spin or orbital Hall current is injected laterally from e.g Pt into Au or from Co or Py into Cu. Work carried out in collaboration with Rohit Nair, Max Rang, K. Gupta, R.J.H. Wesselink, R.X. Liu, Z. Yuan and E. Barati [1] R.J.H. Wesselink et al., PRB 99, 144409 (2019); R.S. Nair and P.J. Kelly, PRB 103, 195406 (2021). [2] A. A. Starikov et al., PRB 97, 214415 (2018). [3] Y. Liu et al., PRB 91, 220405 (2015). [4] R.S. Nair et al. PRL 126, 196601 (2021). [5] K. Gupta et al., PRL 124, 087702 (2020); PRB 104, 205426 (2021); PRB 106, 104401 (2022); PRB 106, 115425 (2022).

05 Oct 2023

GRK 2516 Soft Matter Seminar

Uni Mainz

14:30 Uhr s.t., Minkowski Room, 05-119, Staudingerweg 7

Shan Jaing, Materials Science and Engineering, Iowa State University of Science and Technology, Ames, USA
The race of colloids and nanoparticles near the interface presents interesting transport phenomena and unique opportunities to understand their interactions. Stratification was observed when different species preside over the interfaces in the final dried coating structure. However, previous studies mostly focused on conventional homogeneous colloids. We have synthesized amphiphilic Janus particles and investigated their stratification behaviors. When mixed with homogeneous particles, upon drying Janus particles formed a complete and densely packed monolayer with their hydrophobic sides orienting towards air. This drastically increased the water contact angle of the dried film. Confocal study further revealed that Janus particles vigorously diffused towards interface two orders of magnitude faster than the Brownian motion. To explain these observations, we proposed a mechanism based on consideration of adsorption and surface charges. More importantly, the discovery may lead to new fundamental understanding of nanoparticle interactions near interfaces. The results also suggest a novel approach of fabricating functional surfaces using Janus particle as a coating additive.
at Zoom

09 Oct 2023

INSPIRE Seminars

Uni Mainz

Sonderseminar: 14:00 Uhr s.t., Staudingerweg 7, Room 01-327

Alexander M. Finkel’stein, The Weizmann Institute of Science (Israel) and Texas A&M University (USA)
Wave computations rely on superposition but doesn’t request for entanglement. To utilize the spin waves for fast computing and communications, one needs in controlling the spin waves. (For the wave computations, there should be many waves involved.) A feasible way to manipulate the spin-wave propagation is through the magnonic crystal. Magnonic crystal is a periodic in space modulation, which is analogues to the Bragg mirror in optics. We extended the idea to an AC-magnonic crystal, and showed how it could be used for generating and controlling many tunable “qubits” formed by pairs of mutually scattering spin waves. One can also utilize the AC magnonic crystal for the manipulation of the “qubits” via single-qubit gates of different kinds, thereby, opening new possibilities in the spin-wave computing. In collaboration with Ankang Liu, now at the MSU

Sonderseminar

23 Oct 2023

Seminar about Experimental Particle and Astroparticle Physics (ETAP)

Institut für Physik

12:30 Uhr s.t., Staudingerweg 7, Minkowskiraum

Bastian Keßler, Institut für Physik
Wavelength shifting fibres with high capture rate
at https://indico.him.uni-mainz.de/event/199/

24 Oct 2023

Physikalisches Kolloquium

Institut für Kernphysik

16 Uhr c.t., HS KPH

Prof. Tommaso Calarco, Forschungszentrum Juelich
Quantum optimal control has been shown to improve the performance of quantum technology devices up to their limits in terms e.g. of system size and speed of operation. I will review our recent results with a variety of quantum technology platforms, focusing in particular on ultracold atoms, and introduce our newly developed software for automatic calibration of quantum operations - the fundamental building block of next-generation quantum firmware
Slides here...

Theorie-Palaver

Institut für Physik

14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)

Benoit Assi, Fermilab
The geometry underlying field space plays a pivotal role in governing on-shell scattering amplitudes. In this talk, we present a comprehensive geometric description of effective field theories, building upon prior work involving scalars and gauge fields, and further extending it to fermions. This novel field-space geometry not only offers a systematic reorganization but also significantly streamlines the computation of quantum loop corrections. Capitalizing on this framework, we attain the fermion loop contributions to the renormalization group equations for bosonic operators within the Standard Model Effective Field Theory, covering up to mass dimension eight.

25 Oct 2023

PRISMA+ Colloquium

Institut für Physik

13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

Prof. Dr. Jörg Jaeckel, Heidelberg Univ.
In this talk we start with the classical example of an oscillating cosmological field axion and axion-like particle dark matter. We will see that it is a suitable dark matter candidate, albeit one with interesting wave-like features that express themselves as coherent oscillations. We discuss existing and future probes of this type of dark matter. Following the theme of probing tiny oscillations we go beyond dark matter and even beyond particles and ask whether there could be a fundamental violation of Poincare invariance and study tests of this fundamental symmetry by looking for time-varying and oscillating effects.

26 Oct 2023

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

Institut für Physik

14:00 Uhr s.t., IPH Lorentzraum 05-127

Prof. Dr. Alexandre Obertelli, TU Darmstadt Institut für Kernphysik
Rare isotope facilities have given access to the neutron-rich side of the nuclear landscape. In this seminar, the recent results obtained at the RIBF, RIKEN, on the structure of the most neutron-rich nuclear systems studied so far, 4n and 28O, will be presented together with the challenges faced by ab initio theory. The neutron excess in neutron-rich nuclei develop as a neutron skin or halo at the nuclear surface. The extension of neutrons at the nuclear surface remains relatively unconstrained. The new experiment PUMA (antiProton Unstable Matter Annihilation) at CERN aims at investigating the neutron to proton content of the nuclear density tail of stable and unstable nuclei by use of trapped antiprotons as a probe. The principle and status of the experiment will be given.

Seminar über Theorie der kondensierten Materie / TRR146 Seminar

F. Schmid / G. Settanni / P. Virnau / L. Stelzl

14:30 Uhr s.t., Minkowski Room, 05-119, Staudingerweg 7

Bernd Jung & Gerhard Jung, Independent Scholar, Eltville, Germany & Laboratoire Charles Coulomb (L2C), Université de Montpellier, CNRS, 34095 Montpellier, France
We are generally interested in numerically studying the properties of soft matter. Due to limited computational resources, such studies often have to rely on coarse graining. This is the process of removing microscopic degrees of freedom to find models that are computationally much more efficient but still allow for realistic simulations of static and dynamic characteristics. While structural properties in coarse-grained models can be described and reconstructed by effective potentials, the description of dynamics is even more complex. It requires the introduction of additional dissipative and thermal forces to compensate for the systematic removal of degrees of freedom. One of the open questions in this field is how non-linearities in the underlying system influence form and dynamics of the coarse-grained model. Therefore, we investigated a system in thermal equilibrium using analytical theory, linear and non-linear projection operator formalisms, and computer simulations for a detailed analysis of the impact of such non-linearities. Our study highlights some open challenges and possible solutions in dynamic coarse graining. B. Jung, G. Jung, "Dynamic coarse-graining of linear and non-linear systems: Mori–Zwanzig formalism and beyond", J. Chem. Phys. 159, 084110 (2023), https://doi.org/10.1063/5.0165541

PW: 008795

31 Oct 2023

Physikalisches Kolloquium

Institut für Kernphysik

16:15 Uhr s.t., HS KPH

Prof. Peter Haynes, University of Cambridge
In the last 20 years or so it has been recognised that stratospheric processes have an important effect on the circulation of the troposphere and hence on weather and climate, particularly in the extratropics. The effect is now being exploited in medium range to seasonal weather prediction. The magnitude of the effect is at first surprising given that the mass of stratosphere is only about one fifth of that of the troposphere, but there are important dynamical feedback effects, both in the coupling of troposphere and stratosphere and within the troposphere itself, that amplify the tropospheric response to changes in the stratosphere. This talk will first describe the feedback effects that operate in the extratropics and then move on to consider the tropics, where significant apparent effects of the stratosphere on the troposphere have also become evident. However, the dynamics of the tropical troposphere are very different to that of the extratropical troposphere and it cannot be assumed that the same feedbacks operate in both. Some of the physical and dynamical processes that might account for observed connections between the tropical stratosphere and the tropical troposphere will be discussed.
Slides here...

Theorie-Palaver

Institut für Physik

14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)

Meet and Greet, -
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Seminar Festkörper- und Grenzflächenphysik KOMET - experimentell

Institut für Physik

12:00 Uhr s.t., Newton-Raum, Staudingerweg 9, 1. Stock, Raum 122 (Nebengebäude)

TBA, JGU Mainz
VORBESPRECHUNG

02 Nov 2023

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

Institut für Physik

14:00 Uhr s.t., IPH Lorentzraum 05-127

Prof. Dr. Jörn Müller-Quade, KIT Karlsruhe Kryptographie & Sicherheit
Classical cryptographic tasks, like key distribution, need computational assumptions and are vulnerable to attacks breaking these assumptions in the future. Classical security is not everlasting. For key distribution Quantum Cryptography offers a huge advantage, unconditionally secure protocols are possible. This success, however, could not be repeated for other important cryptographic tasks, e.g. bit commitment or coin tossing. What is more, it could even be proven that all cryptographic tasks which are sufficent for confidential computing cannot be realized with unconditional security even if a quantum channel is available. This no-go result overshadowed the research on confidential computing with quantum cryptography and the term quantum cryptography is now largely seen as a synonym for quantum key distribution. This talk shows that in spite of the no-go theorems there still are advantages of quantum cryptography over classical solutions. In particular the talk will present a yet unpublished result, that under therealistic assumption that quantum storage has a limited lifetime “everlasting security” can be achieved. I.e. computational assumptions are still needed, but the cryptographic protocol eventually becomes unconditionally secure after the quantum information used has decayed.

GRK 2516 Soft Matter Seminar

Uni Mainz

14:30 Uhr s.t., Minkowski Room, 05-119, Staudingerweg 7

Vishal Maingi, Bioengineering, Caltech
TBA
at Zoom

Seminar über Theorie der kondensierten Materie / TRR146 Seminar

F. Schmid / G. Settanni / P. Virnau / L. Stelzl

14:30 Uhr s.t., Online

Vishal Maingi, Bioengineering, Caltech
GRK 2516 Soft Matter Seminar

PRISMA+ Colloquium

Institut für Physik

Sonderseminar: 13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

Robert Svoboda, UC Davis, USA
The Far Detectors for the Deep Underground Neutrino Experiment (DUNE) are currently under construction at the Sanford Underground Research Facility (SURF), set to begin operations in about four years. While designed primarily to reconstruct GeV-scale neutrino interactions to look for CP violation, some unique properties of argon make solar and supernova burst neutrino measurements particularly interesting. I will discuss why this is so interesting, why an argon detection media is so unique, and what could be the limiting backgrounds. Link to Presentation Slides: https://docs.google.com/presentation/d/1rSApQOsGt0T87olMUTKhVMMJq0kXr0G9/edit?usp=sharing&ouid=103217522426961737580&rtpof=true&sd=true

Sonderseminar

06 Nov 2023

Seminar about Experimental Particle and Astroparticle Physics (ETAP)

Institut für Physik

12:30 Uhr s.t., Staudingerweg 7, Minkowskiraum

Vsevolod Orekhov, Institut für Physik
Development of comprehensive analysis tools for SN neutrino detection
at https://indico.him.uni-mainz.de/event/199/

07 Nov 2023

Physikalisches Kolloquium

Institut für Kernphysik

16:15 Uhr s.t., HS KPH

CANCELED: Dr. Axel Lindner, Deutsches Elektronen-Synchrotron (DESY)
We hereby would like to inform you that the colloquium on November 7th, 2023 has been cancelled due to an important commitment of the speaker Alex Lindner. He has been invited to a podium discussion with streaming on youtube on 7 November 19:00 h https://www.desy.de/aktuelles/oeffentliche_abendvortraege/hamburg/index_ger.html Feel free to attend it if you would like (link can be found on the above web page). We are working towards getting Alex Lindner to Mainz in the SoSe 2024.

Theorie-Palaver

Institut für Physik

14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)

Encieh Erfani, JGU Mainz
In this presentation, I will elucidate the mechanisms behind Primordial Black Hole formation, discuss their potential role as candidates for dark matter, explore their significance as gravitational wave sources, and delve into the methodologies employed for their detection.

Seminar Festkörper- und Grenzflächenphysik KOMET - experimentell

Institut für Physik

12:00 Uhr s.t., Newton-Raum, Staudingerweg 9, 1. Stock, Raum 122 (Nebengebäude)

PRELIMINARY DISCUSSION, JGU
TBA

08 Nov 2023

PRISMA+ Colloquium

Institut für Physik

13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

Prof. Dr. Marco Serone, SISSA, Italy
Perturbation theory is one of the most important analytical tool in quantum mechanics and quantum field theory, but it is known to give rise to divergent asymptotic series. How can we then make sense out of it? Resurgence seems to be a possible answer. After an historical detour on the study of the asymptotic behaviour of perturbation theory, we introduce basic notions of resurgence and show some application in quantum mechanics and quantum field theory.
Slides here...

09 Nov 2023

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

Institut für Physik

14:00 Uhr s.t., IPH Lorentzraum 05-127

Dr. Hendrik Poulsen Nautrup & Dr. Sofiène Jerbi, Universität Innsbruck Institut für Theoretische Physik
Measurement-based quantum computation (MBQC) offers a fundamentally unique paradigm to design quantum algorithms. Indeed, due to the inherent randomness of quantum measurements, the natural operations in MBQC are not deterministic and unitary, but are rather augmented with probabilistic byproducts. Yet, the main algorithmic use of MBQC so far has been to completely counteract this probabilistic nature in order to simulate unitary computations expressed in the circuit model. In this talk, we are going to introduce MBQC as an ansatz for parameterized learning models that embraces this inherent randomness and treat random byproducts in MBQC as a resource for computation. We demonstrate numerically, that such models can lead to significant gains in learning performance in certain generative modeling tasks. We finish with a proposal for an experimental implementation of such an MBQC-based learning model for shuttling-based ion traps.

Seminar über Theorie der kondensierten Materie / TRR146 Seminar

F. Schmid / G. Settanni / P. Virnau / L. Stelzl

14:30 Uhr s.t., Minkowski Room, 05-119, Staudingerweg 7

Hendrik Jung, FU Berlin
AI for Molecular Mechanism Discovery (aimmd)

PW: 008795

13 Nov 2023

Seminar about Experimental Particle and Astroparticle Physics (ETAP)

Institut für Physik

12:30 Uhr s.t., Staudingerweg 7, Minkowskiraum

Claudia Delogu, Institut für Physik
Calorimeters for particle identification
at https://indico.him.uni-mainz.de/event/199/

14 Nov 2023

Physikalisches Kolloquium

Institut für Kernphysik

16 Uhr c.t., HS KPH

Prof. Yoichiro Tanaka, Tohoku University, Japan
The digital world is producing nearly a hundred Zetta bytes of data per year and creating values for the quality of society. A huge amount of data is being stored, processed, transmitted, and then shared via large scale networked datacenters which consist of millions of data storage systems filled with perpendicular magnetic recording (PMR) hard disk drives. The PMR technology was invented by Shunichi Iwasaki in 1975 and the first commercial product was launched in 2005. Since then, the data storage has become the ever-growing foundation of the digital world and led the data-driven innovations such as bigdata AI analytics, internet of things, medical science, and even a blackhole visualization in astronomy. This lecture will provide the essential magnetics to create innovative data storage technology of PMR and the origin of the high-density recording performance which has led current recording density growth. The storage performance stands on the stacked system foundation and the building blocks are, from the base, physics of magnetics, 3D material controls of sub-nanometer in size, magnetic and electronic device design, storage device integration, and storage system architectures together with non-volatile memories to unleash the intrinsic performance. The development of new storage devices and the system requires a multi-scale approach and a right guiding principle to establish expected functions. As an extension of PMR research, the lecture will also show the prospect of future storage technology and the system architecture from the multi-scale view of the storage system development. A new computational storage system aiming at unifying computation power on data store and brain-inspired system considerations as well as the academism-industry relations to realize those systems will also be introduced.
Slides here...

Theorie-Palaver

Institut für Physik

14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)

Helena Kolešová, University of Stavanger
Taking axion inflation as an example, we study the evolution of a non-Abelian dark sector coupled to the inflaton for different choices of the confinement scale. Gravitational wave signals could be in principle generated due to a confinement phase transition or fluctuations in the thermal plasma, however, these signals might be strongly suppressed due to the presence of an early matter-dominated era. We also study the reheating of Standard Model fields and explore the possibility of glueball dark matter within this scenario.

Seminar Festkörper- und Grenzflächenphysik KOMET - experimentell

Institut für Physik

12:00 Uhr s.t., Newton-Raum, Staudingerweg 9, 1. Stock, Raum 122 (Nebengebäude)

TBA, TBA
TBA

15 Nov 2023

PRISMA+ Colloquium

Institut für Physik

13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

Prof. Dr. Gianpaolo Carosi, Lawrence Livermore National Lab, USA
The axion is a hypothetical particle that may solve two problems in particle physics & cosmology, the Strong-CP problem (or why the neutron doesn’t have a measurable electric dipole moment) and the nature of dark matter. The Axion Dark Matter Experiment (ADMX), which started at Lawrence Livermore National Laboratory in the mid-1990s and has gone through a series of upgrades through the years, is the DOE Flagship search for these particles. The experiment uses tunable resonant cavities in a large static magnetic field to enhance the conversion of dark matter axions to detectable microwaves. Quantum-limited amplifiers based on superconducting Josephson Junction circuits are critical to allow the search to be sensitive enough to rapidly scan the frequencies where the axion may exist. Here I will describe the detection strategy of ADMX, the progress made so far, and outline the next phase of the experiment dubbed ADMX-Extended Frequency Range (ADMX-EFR), which aims to cover 2-4 GHz at below DFSZ sensitivity. Opportunities for physics searches beyond axions, such as potentially high frequency gravity waves, will also be discussed.
Slides here...

16 Nov 2023

GRK 2516 Soft Matter Seminar

Uni Mainz

14:30 Uhr s.t., Minkowski Room, 05-119, Staudingerweg 7

Marcus Müller, Institute for Theoretical Physics, Uni Göttingen
Simulation studies of process-directed self-assembly
at Zoom

Seminar über Theorie der kondensierten Materie / TRR146 Seminar

F. Schmid / G. Settanni / P. Virnau / L. Stelzl

14:30 Uhr s.t., Minkowski Room, 05-119, Staudingerweg 7

Marcus Müller, Institute for Theoretical Physics, Uni Göttingen
GRK 2516 Soft Matter Seminar

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

Institut für Physik

14:00 Uhr s.t., IPH Lorentzraum 05-127

Prof. Dr. Wilfried Nörtershäuser, TU Darmstadt Institut für Kernphysik
Nuclear charge radii of radioactive isotopes are typically referenced to a stable nucleus in the isotopic chain through an atomic isotope shift measurement. In some cases, this can limit the uncertainty of the obtained charge radii of radioactive nuclei to the uncertainty of the reference measurements from elastic electron scattering or muonic atom spectroscopy. To overcome this limit in light mass nuclei like 10,11B, an all-optical approach for the charge radius determination purely from laser spectroscopy measurements and non-relativistic QED calculations was tested with the well-known nucleus of 12C through laser excitation of helium-like 12C4+ from the metastable 2 3S1 state with a lifetime of 21 ms to the 2 3P𝐽 states. The high-precision collinear laser spectroscopy of 12C4+ has been performed at the Collinear Apparatus for Laser Spectroscopy and Applied Physics (COALA) at at TU Darmstadt in the Institute of Nuclear Physics and meanwhile extended to 13C4+. I will give an overview of the project and present the results including the extracted all-optical nuclear charge radius of 12C. An outlook on planned measurements at COALA and a potential application on short-lived isotopes at ISOLDE will be provided. This project is supported by DFG (Project-ID 279384907 - SFB 1245).

20 Nov 2023

Seminar about Experimental Particle and Astroparticle Physics (ETAP)

Institut für Physik

12:30 Uhr s.t., Staudingerweg 7, Minkowskiraum

Ioana Caracas, Institut für Physik
DUNE-PRISM: An innovative technique for neutrino oscillation analysis
at https://indico.him.uni-mainz.de/event/199/

21 Nov 2023

Physikalisches Kolloquium

Institut für Kernphysik

16:15 Uhr s.t., HS KPH

Prof. Kenneth Long, Imperial College UK
The ‘Laser-hybrid Accelerator for Radiobiological Applications’, LhARA, is conceived as a novel, uniquely flexible facility dedicated to the study of radiobiology. The technologies that will be demonstrated in LhARA have the potential to allow particle-beam therapy to be delivered in a completely new regime, combining a variety of ion species in a single treatment fraction and exploiting ultra-high dose rates. LhARA will be a hybrid accelerator system in which laser interactions drive the creation of a large flux of protons or light ions that are captured using a plasma lens and formed into a beam. Serving the Ion Therapy Research Facility (ITRF), the laser-hybrid approach will allow the exploration of the vast “terra incognita” of the mechanisms by which the biological response is modulated by the physical characteristics of the beam. I will describe the motivation for LhARA, present the status of its development and summarise the programme upon which the LhARA consortium has embarked to drive a step-change in clinical capability.
Slides here...

Theorie-Palaver

Institut für Physik

14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)

Maeve Madigan, Heidelberg U.
The Standard Model Effective Field Theory (SMEFT) provides a powerful theoretical framework for interpreting subtle deviations from the Standard Model and searching for heavy new physics at the LHC. Accurate interpretations of LHC data, however, rely on the precise knowledge of the proton structure in terms of parton distribution functions (PDFs). In this seminar, I will discuss the interplay between PDFs and the search for new physics. I will showcase a scenario for the High-Luminosity LHC in which the PDFs may completely absorb such signs of new physics, thus biasing theoretical predictions and interpretations. To address this challenge, I will present a simultaneous determination of PDFs and the SMEFT using the SIMUnet methodology. This approach integrates both PDF and SMEFT determinations into a single, coherent framework, making possible an assessment of the regions of parameter space in which the interplay is most phenomenologically relevant, both at the LHC and HL-LHC.

Seminar Festkörper- und Grenzflächenphysik KOMET - experimentell

Institut für Physik

12:00 Uhr s.t., Newton-Raum, Staudingerweg 9, 1. Stock, Raum 122 (Nebengebäude)

TBA, TBA
TBA

22 Nov 2023

PRISMA+ Colloquium

Institut für Physik

13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

Dr. Monica Dunford, Heidelberg Univ.
The dynamics of the Standard Model of particle physics play a central role in the properties of not only the microscopic world but also the biggest structures of our universe. The Higgs boson, for example, plays a critical part in how particles obtain their masses but also perhaps to dark matter and how our universe evolved. In this talk, the referent will focus on some key measurements that can be done with the on-going Run 3 data at the LHC and their impact on our understanding of particle physics. She will highlight how these results have connections beyond the microscopic world to dark matter, matter and anti-matter differences and beyond. In addition, she will touch upon future technology developments that will allow us to explore these connections even further.

23 Nov 2023

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

Institut für Physik

14:00 Uhr s.t., IPH Lorentzraum 05-127

Dr. Nils Huntemann, PTB Nationales Metrologieinstitut
The 171Yb+ ion features two narrow optical transitions: an electric octupole (E3) transition as well as an electric quadrupole (E2) transition. Both transitions are suitable for the realization of an optical clock and accepted as secondary representations of the SI unit second and a composite system that relies on the spectroscopic information provided by both transitions can even provide superior clock performance. Because both transitions also show a large differential sensitivity to the fine structure constant á, its possible variations can be probed by comparing the transition frequencies at various positions in spacetime. We find improved bounds on a linear temporal drift of á, as well as its coupling to the gravitational potential of the sun, from a long-term optical clock comparison [1,2]. Additionally, the couplings of so-called ultralight bosonic dark matter (m « 1 eV/c^2) to standard model particles would lead to coherent oscillations of constants, with an oscillation frequency corresponding to the Compton frequency of the dark matter mass [3]. We conduct a broadband dark-matter search by comparing the frequency of the E3 transition to that of the E2 transition, and to that of the 1S0 ↔ 3P0 transition in 87Sr. We find no indication for significant oscillations in our experimental data. Consequently, we put limits on oscillations of the fine-structure constant and thus improve existing bounds on the scalar coupling of ultralight dark matter to photons for dark-matter masses of about 1E−24 to 1E−17 eV/c^2 [2]. Couplings to quarks and gluons can also be investigated with optical frequency ratio measurements by considering the effect an oscillating nuclear charge radius would have on electronic transitions [4]. Finally, I will report on our efforts towards clocks in which co-trapped 88Sr+ ions [5] enable even superior 171Yb+ clock performance. [1] Lange et al., Phys. Rev. Lett. 126, 011102 (2021). [2] Filzinger et al., Phys. Rev. Lett. 130, 253001 (2023). [3] Arvanitaki et al., Phys. Rev. D 91, 015015 (2015). [4] Banerjee et al., arXiv:2301.10784 (2023). [5] Steinel et al., Phys. Rev. Lett. 131, 083002 (2023).

28 Nov 2023

Physikalisches Kolloquium

Institut für Kernphysik

16 Uhr c.t., HS KPH

Prof. Eberhard Bodenschatz, MPI for Dynamics and Self-Organization, Göttingen
82 years ago, the mathematician Andrei Nikolayevich Kolmogorov postulated that a turbulent flow should have universal statistical self-similar properties. Independently, the flow researcher Ludwig Prandtl concluded similar results 4 years later. Nobel laureates Werner von Heisenberg and Carl-Friedrich von Weizsäcker and Lars Onsager each came to the same conclusion shortly thereafter. Over the years, the expected power laws have been refined, but it has not been possible to measure them at very high turbulence level necessary. Simulations of driven turbulence on the world's largest computers provide evidence of this statistical universality. These simulations are highly idealized, they live in a periodic box, and the energy is introduced globally on large scales. Experimentally, this kind of turbulent flow is not feasible. So the question is: what do experiments show? For more than 100 years, the wind tunnel has been the canonical flow regime for turbulence research. When a fluid flows through a grid at high velocity, vortices form and decay after a short time; the flow then exhibits the universal statistical properties of turbulence. Today, electronics are highly optimized and there are the smallest hotwires made with advanced nanotechnology. This also makes it possible to measure velocities on the smallest length scales. However, very high turbulence intensity is required to measure universal static properties. In the past, experiments were mainly performed with air (hence the name wind tunnel). When using air at atmospheric pressure, the wind tunnel would have to be huge in diameter to achieve extremely high turbulence intensity to test Kolmogorov like theories. This is where the Variable Density Turbulence Tunnel (VDTT) at the Max Planck Institute for Dynamics and Self-Organization comes in. Among others, I will present recent results showing that universality is found, albeit with spatially dependent logarithmic dependence of the power-law exponents.
Slides here...

Theorie-Palaver

Institut für Physik

14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)

Stefano De Angelis, IPhT, Saclay
In the first part of the seminar, I will review some recent progress made using modern on-shell techniques to understand (relativistic) EFTs and uncover hidden structures, with a particular focus on the SMEFT (from a purely on-shell construction of EFTs to selection rules in cross-section and RG equations). Motivated by this recent progress, in the second part, I will present a new on-shell formula for the matching of ultraviolet models featuring massive states onto their massless effective field theory. This formula is based on a dispersion relation in the space of complex momentum dilations to capture, in a single variable, the relevant analytic structure of scattering amplitudes at any multiplicity.

Seminar Festkörper- und Grenzflächenphysik KOMET - experimentell

Institut für Physik

12:00 Uhr s.t., Newton-Raum, Staudingerweg 9, 1. Stock, Raum 122 (Nebengebäude)

Tobias Sparmann, JGU
TBA

29 Nov 2023

PRISMA+ Colloquium

Institut für Physik

13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

Prof. Dr. Laura Lopez Honorez, Univ. Brussels, Belgium
Compelling data from Cosmology tell us that more than 80% of the matter content of the universe is made of Dark Matter (DM). Yet the fundamental properties of DM is still unknown. In my talk, I will assume that DM is a particle beyond the Standard Model of Particle physics. You usually hear that DM should be cold and not hot. Yet it can be warm. The referent will discuss under which condition "non-cold" dark matter can be a good candidate to account for all the DM. In this framework, she will briefly present different mechanisms for dark matter production. She will also show that, even when dark matter interacts very feebly with visible matter, the interplay between particle physics and cosmology experiments is a key in probing the dark matter nature.
Slides here...

30 Nov 2023

GRK 2516 Soft Matter Seminar

Uni Mainz

14:30 Uhr s.t., Minkowski Room, 05-119, Staudingerweg 7

Dijkstra, Marjolein, Computational Condensed Matter, Utrecht University
Predicting the emergent properties of a material from a microscopic description is a scientific challenge. Machine learning and reverse-engineering have opened new paradigms in the understanding and design of materials. However, this approach for the design of soft materials is highly non-trivial. The main difficulty stems from the importance of entropy, the ubiquity of multi-scale and many-body interactions, and the prevalence of non-equilibrium and active matter systems. The abundance of exotic soft-matter phases with (partial) orientation and positional order like liquid crystals, quasicrystals, plastic crystals, along with the omnipresent thermal noise, makes the classification of these states of matter using ML tools highly non-trivial. In this talk, I will address questions like: Can we use machine learning to autonomously identify local structures [1,2], detect phase transitions [1], classify phases and find the corresponding order parameters [2], can we identify the kinetic pathways for phase transformations [1], and can we use machine learning to coarse-grain our models [3,4,5]? Finally, I will show in this lecture how one can use machine learning to reverse-engineer the particle interactions to stabilize nature’s impossible phase of matter, namely quasicrystals [6]? [1] An artificial neural network reveals the nucleation mechanism of a binary colloidal AB13 crystal G.M. Coli and M. Dijkstra, ASC Nano 15, 4335-4346 (2021). [2] Classifying crystals of rounded tetrahedra and determining their order parameters using dimensionality reduction R. van Damme, G.M. Coli, R. van Roij, and M. Dijkstra, ACS Nano 14, 15144-15153 (2020). [3] Machine learning many-body potentials for colloidal systems G. Campos-Villalobos, E. Boattini, L. Filion and M. Dijkstra, The Journal of Chemical Physics 155 (17), 174902 (2021). [4] Machine-learning effective many-body potentials for anisotropic particles using orientation-dependent symmetry functions G. Campos-Villalobos, G. Giunta, S. Marín-Aguilar and M. Dijkstra, The Journal of Chemical Physics 157 (2), 024902 (2022). [5] Coarse-Grained Many-Body Potentials of Ligand-Stabilized Nanoparticles from Machine-Learned Mean Forces G. Giunta, G. Campos-Villalobos, and M. Dijkstra, ACS Nano (2023). [6] Inverse design of soft materials via a deep learning–based evolutionary strategy G.M. Coli, E. Boattini, L. Filion, and M. Dijkstra, Science Advances 8 (3), eabj6731 (2022).
at Zoom

Seminar über Theorie der kondensierten Materie / TRR146 Seminar

F. Schmid / G. Settanni / P. Virnau / L. Stelzl

14:30 Uhr s.t., Minkowski Room, 05-119, Staudingerweg 7

Marjolein Dijkstra, Computational Condensed Matter, Utrecht University
GRK 2516 Soft Matter Seminar

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

Institut für Physik

14:00 Uhr s.t., IPH Lorentzraum 05-127

Prof. Dr. Catalina Curceanu, INFN, Rom/Italy
We are experimentally investigating possible departures from the standard quantum mechanics’ predictions at the Gran Sasso underground laboratory in Italy. In particular, with refined radiation detectors, we are searching signals predicted by the dynamical collapse models (spontaneous emission of radiation) which were proposed to solve the “measurement problem” in quantum physics, and signals indicating a possible violation of the Pauli Exclusion Principle. I shall discuss our recent results which ruled out the natural parameter-free version of the gravity-related collapse model. I shall then present more generic results on testing CSL (Continuous Spontaneous Localization) collapse models and discuss future perspectives. Finally, I shall present the VIP experiment, with which we search for possible violations of the Pauli Exclusion Principle manifested as “impossible” atomic transitions, and muse about the impact of this research in relation to Quantum Gravity models.

01 Dec 2023

THEP Journal Club

Institut für Physik

12:30 Uhr s.t., Minkowski Raum, Staudinger Weg 7, 05-119

Anke Biekötter, JGU Mainz
SMEFT Analyses for New Physics (TBA)

05 Dec 2023

Physikalisches Kolloquium

Institut für Kernphysik

16 Uhr c.t., HS KPH

Dr. Urmi Ninad, TU Berlin
Statistical inference aims to fit observed data into a model that explains the data and is able to make predictions. However, as we are repeatedly told, ‘correlation does not imply causation’, therefore robust prediction and reasoning about underlying processes governing the data distribution cannot be done by relying on observed statistical dependences alone. Causal reasoning aims to formalise the setting under which causal, rather than merely statistical, relationships can be inferred from observed data, thereby making the learned model more indicative of the true underlying process. In the last decade, the field of causal inference has gained immense popularity in the statistics and machine learning communities to develop and utilise this framework on the one hand, and in application domains such as economics, genetics and climate to use causal algorithms to practical problems of interest on the other hand. In this talk, I will lay the foundations of causal inference, explain the various approaches to do causal inference that have emerged in the recent years, and close the talk with examples of application of the causality framework to climate science.
Slides here...

Seminar Festkörper- und Grenzflächenphysik KOMET - experimentell

Institut für Physik

12:00 Uhr s.t., Newton-Raum, Staudingerweg 9, 1. Stock, Raum 122 (Nebengebäude)

TBA, TBA
TBA

Theorie-Palaver

Institut für Physik

14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)

Maura Ramirez Quezada, JGU Mainz
In this talk, I'll explore the potential of using white dwarfs as cosmic laboratories to investigate hidden interactions beyond the Standard Model. My focus will be on the cooling process of white dwarfs, specifically through neutrino emission, and investigate the impact of a dark photon in a three-portal model on the neutrino emission during white dwarf cooling.

06 Dec 2023

PRISMA+ Colloquium

Institut für Physik

13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

Dr. Haakon Andresen, Univ. Stockholm, Sweden
The referent will give a broad overview of current core-collapse supernova theory and highlight important challenges for the future. Currently, numerical simulations produce successful explosion, but this is only the first required step in order to understand the role of core-collapse supernovae in the wider astrophysical and cosmological picture. He will discuss the underlying uncertainties in the input physics, such as neutrino transport and stellar evolution. The refernent will also summarize the current predictions for the gravitational waves and neutrino signals expected from core-collapse supernovae.

07 Dec 2023

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

Institut für Physik

14:00 Uhr s.t., IPH Lorentzraum 05-127

Dr.-Ing. Steffen Kurth, Fraunhofer Institut for Electronic Nano Systems ENAS
The ion trap chip is considered to be the heart of quantum computing based on trapped ions. An ideal case is to have available a devices with all sub-components that are necessary for the operation in a small package. First approaches to fabricated integrated miniaturized ion traps are followed by different groups worldwide. Latest directions are to combine multiple registers, that are connected to each other, to use micro optical components such as micro lenses or even photonic integrated circuits for coupling laser radiation to the ions, to integrate photo detectors (e.g. single photon avalanche diodes) close to or within the ion trap chip. The integration of electronic components (e.g. digital/analog-converters) to provide the electric potentials for the trap electrodes is a further goal that becomes an enabler for integrated ion traps with a higher number of registers. This talk will show how wafer level micro technologies contribute to the above described target. It starts with the vision of an integrated ion trap. Wafer level technologies for fabricating of the different layers are discussed. It covers different material deposition procedures and etching. A next section is about optical sub-components and their manufacturing procedures. Furthermore, a broad variety of assembly technologies and of ways for electric signal routing and connecting is shown with examples.

Seminar über Theorie der kondensierten Materie / TRR146 Seminar

F. Schmid / G. Settanni / P. Virnau / L. Stelzl

14:30 Uhr s.t., Minkowski Room, 05-119, Staudingerweg 7

Achim Klenke, JGU, Chemistry
Mean Number of Visible Confetti

PW: 146146

Theorie-Palaver

Institut für Physik

10:30 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)

Kristina Giesel, FAU Erlangen
Accessing the physical sector in models of quantum gravity is on the one hand a challenge, but on the other hand also an important step to be able to analyse and test such models. One way to complete the quantisation programme in loop quantum gravity is to choose dynamical reference systems so-called matter or geometric clocks for which Dirac observables can be constructed in the framework of the relational formalism. The quantisation step then consists in finding representations for the corresponding algebra of Dirac observables that allow one to quantise the dynamics as well. In this way, one obtains an observer-dependent quantum field theory. We will give a brief overview of the existing models and discuss their similarities and differences. Finally, we will discuss examples for investigating some physical properties of models formulated with a particular choice of clocks in cosmology and open quantum systems in which gravitationally induced decoherence is present.

11 Dec 2023

Seminar about Experimental Particle and Astroparticle Physics (ETAP)

Institut für Physik

12:30 Uhr s.t., Staudingerweg 7, Minkowskiraum

Chen Wang, Institut für Physik
Precision Measurements of the effective weak-mixing angle and the W-boson mass
at https://indico.him.uni-mainz.de/event/199/

12 Dec 2023

Physikalisches Kolloquium

Institut für Kernphysik

16:15 Uhr s.t., HS KPH

No Colloquium, ---
(Lecture Hall is occupied)

Seminar Festkörper- und Grenzflächenphysik KOMET - experimentell

Institut für Physik

12:00 Uhr s.t., Newton-Raum, Staudingerweg 9, 1. Stock, Raum 122 (Nebengebäude)

TBA, TBA
TBA

Theorie-Palaver

Institut für Physik

14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)

Gael Finauri, TU München
Light-cone distribution amplitudes (LCDAs) frequently arise in factorization theorems involving light and heavy mesons. The QCD LCDA for heavy mesons includes short-distance physics at energy scales of the heavy quark mass. In this talk I will explain how to achieve the separation of this perturbative scale from the purely hadronic effects by expressing the QCD LCDA as a convolution of a perturbative « jet » function with the universal, quark-mass independent HQET LCDA. This factorization allows to efficiently resum large logarithms between Lambda QCD and m_Q as well as between m_Q and the scale of the hard process in the production of boosted heavy mesons at colliders. As an application I will present updated theoretical predictions for the brancing ratio of W -> B \gamma.

13 Dec 2023

PRISMA+ Colloquium

Institut für Physik

13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

Prof. Dr. Elina Fuchs, Univ. Hannover
New Physics Searches in the Spectra of Atoms and Ions

Seminar über die Physik der kondensierten Materie (SFB/TRR173 Spin+X und SFB/TR288 Kolloquium, TopDyn-Seminar)

JGU

13:00 Uhr s.t., 01-122 Newton Raum

Dr. Jun'ichi Ieda, Japan Atomic Energy Agency (JAEA)
Emergent inductance appears universally when magnetization dynamics is coupled with conduction electrons based on a sequential action of spin torque and spinmotive force effects under ac currents. An original version of the emergent inductor using > a spiral magnet[1-4] can be extended to include the spin-orbit coupling effects[5,6]. A striking common feature among emergent inductors is their size dependence of the effect; the inductance is inversely proportional to the sample cross-sectional area, opening > a way for integrating an inductor element into nanocircuits. > > 1. Nagaosa, N. “Emergent inductor by spiral magnets,” Jpn. J. Appl. Phys., Vol. 58, 120909, 2019. > 2. Yokouchi, T. et al., “Emergent electromagnetic induction in a helical-spin magnet,” Nature, Vol. 586, 232-236, 2020. > 3. Ieda, J. and Y. Yamane, “Intrinsic and extrinsic tunability of Rashba spin-orbit coupled emergent inductors,” Phys. Rev. B, Vol. 103,. L100402, 2021. > 4. Kitaori, A. et al., “Emergent electromagnetic induction beyond room temperature,” Proc. Natl. Acad. Sci. U.S.A., Vol. 118, e2105422118, 2021. > 5. Yamane, Y., S. Fukami, and J. Ieda, “Theory of emergent inductance with spin-orbit coupling effects,” Phys. Rev. Lett., Vol. 128, 147201, 2022. > 6. Araki, Y. and J. Ieda, “Emergence of inductance and capacitance from topological electromagnetism,” J. Phys. Soc. Jpn., Vol. 92, 074705, 2023.

SFB Sonderseminar

14 Dec 2023

GRK 2516 Soft Matter Seminar

Uni Mainz

17:00 Uhr s.t., Lorentz Room, 05-127, Staudingerweg 7

Florian Mast, JGU, Chemistry
Improving electrochemical reductions: finding the right supporting electrolyte through principal component analysis
at Zoom

Seminar über Theorie der kondensierten Materie / TRR146 Seminar

F. Schmid / G. Settanni / P. Virnau / L. Stelzl

14:30 Uhr s.t., Lorentz Room, 05-127, Staudingerweg 7

Florian Mast, JGU, Chemistry
GRK 2516 Soft Matter Seminar – Improving electrochemical reductions: finding the right supporting electrolyte through principal component analysis

18 Dec 2023

Seminar about Experimental Particle and Astroparticle Physics (ETAP)

Institut für Physik

12:30 Uhr s.t., Staudingerweg 7, Minkowskiraum

Savitri Gallego, Institut für Physik
The Compton Spectrometer and Imager (COSI)
at https://indico.him.uni-mainz.de/event/199/

19 Dec 2023

Physikalisches Kolloquium

Institut für Kernphysik

16:15 Uhr s.t., HS KPH

Prof. Marialuisa Aliotta, University of Edinburgh
The Laboratory for Underground Nuclear Astrophysics (LUNA), located under 1.4km of rock under the Gran Sasso Mountain in central Italy, provides an ideal location for nuclear reaction studies of astrophysical interest. Thanks to its million-fold reduction in cosmic-induced background, LUNA affords unique opportunities to push reaction measurements to the lowest accessible energies. For over 30 years, the LUNA collaboration has thus pioneered studies of nuclear burning processes (pp-chain, CNO-, NeNa- and AlMg-cycles) directly at the relevant astrophysical energies, often for the first time [1]. In some cases, these efforts have led to remarkable results, such as for example the increased age of the universe, and have translated into a better understanding of stellar nucleosynthesis and the chemical evolution of our galaxy. In my talk, I will review some of the major highlights of LUNA’s activity and present exciting new opportunities for upcoming studies of helium- and carbon-burning reactions at the recently installed 3.5MV accelerator. [1] M. Aliotta, A. Boeltzig, R. Depalo, G. Gyurky, Ann. Rev. of Nucl. Part. Sci. 72 (2022) 177-204 [2] G. Imbriani, et al. A&A 420, 625–629 (2004)
Slides here...

Seminar Festkörper- und Grenzflächenphysik KOMET - experimentell

Institut für Physik

12:00 Uhr s.t., Newton-Raum, Staudingerweg 9, 1. Stock, Raum 122 (Nebengebäude)

TBA, TBA
TBA

Theorie-Palaver

Institut für Physik

14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)

Andrea Sanfilippo, TU München
The description of light and massless scalar fields in an inflationary spacetime is of phenomenological interest, as they provide compelling candidates for the inflaton field. During most of the inflationary epoch, the spacetime can be approximated by the de Sitter spacetime, and the observables of interest are in-in correlation functions of fields in de Sitter space, evaluated at late times. However, the computation of these quantities is challenging, particularly when loop corrections are taken into account. In this talk, I will discuss the recently proposed Soft de Sitter Effective Theory (SdSET) as an avenue to address these difficulties. I will then show how the Method of Regions can be used as a powerful tool to construct the late-time expansion of in-in correlators, as well as to gain further insight into the structure of SdSET.

21 Dec 2023

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

Institut für Physik

14:00 Uhr s.t., IPH Lorentzraum 05-127

Prof. Jörg Pretz, Forschungszentrum Jülich
Electric Dipole Moments (EDMs) of elementary particles, including hadrons, are considered as one of the most powerful tool to study CP-violation beyond the Standard Model. Such CP-violating mechanisms are searched for to explain the dominance of matter over anti-matter in our universe. Hypothetical dark matter particles, like axions or axion-like-particles, induce an oscillating EDM. EDMs of charged particles can be measured in storage rings. Due to an EDM, the spin vector will experience a torque resulting in a change of the original spin direction which can be determined with the help of a polarimeter. Although the principle of the measurement is simple, the smallness of the expected effect makes this a challenging experiment requiring new developments in various experimental areas. The talk will focus on first results obtained at the Cooler Synchrotron COSY at Forschungszentrum Jülich and will also discuss future plans.

Seminar Festkörper- und Grenzflächenphysik KOMET - experimentell

Institut für Physik

12 Uhr c.t., Medienraum, Staudingerweg 7, 3. Stock, Raum 03-431

David Anthofer, JGU Mainz
Probing spin-orbit coupling at molecule/metal thin-film interfaces

09 Jan 2024

Physikalisches Kolloquium

Institut für Kernphysik

16:15 Uhr s.t., HS KPH

Prof. Dr. Markus Roth, TU Darmstadt
With the recent demonstration of fusion ignition and burn and the first energy gain from controlled fusion reactions, the laser-based fusion approach has become a promising concept for fusion energy. While not supported in Germany until a few years ago, Germany has a huge potential in taking the lead on laser-fusion research, based on its excellent science and technology in optics and lasers. Focused Energy is a US/German Startup company, spin-off of the TU Darmstadt that has gathered the world experts in laser fusion in the last two years. I will review the recent results at the Lawrence Livermore National Laboratory National Ignition Facility and sketch a pathway from this groundbreaking result to a first fusion reactor prototype.
Slides here...

Seminar Festkörper- und Grenzflächenphysik KOMET - experimentell

Institut für Physik

12:00 Uhr s.t., Newton-Raum, Staudingerweg 9, 1. Stock, Raum 122 (Nebengebäude)

TBA, TBA
TBA

Theorie-Palaver

Institut für Physik

14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)

Zeno Capatti, U. Bern
In this talk, I will review the main aspects of three-dimensional approaches to the computation of Feynman diagrams and of the Local Unitarity formalism. I will start by discussing the Cross-Free Family representation, which allows for a systematic analysis of the singularities of Feynman diagrams. I will then introduce the Local Unitarity framework, in which interference diagrams are combined, through a generally-applicable mapping of the phase-space measure, to give locally finite cross-sections. Finally, I will discuss the extension of the Local Unitarity formalism to processes with initial state singularities, which will allow me to discuss the role of spectator particles and higher-multiplicity initial-state partonic configurations in the cancellation and factorisation of singularities.

10 Jan 2024

PRISMA+ Colloquium

Institut für Physik

13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

Dr. Andrea Caputo, CERN, Switzerland
All the burning questions of the Standard Model such as the origin of dark matter, of the matter antimatter asymmetry, of neutrino masses, seem to invoke the presence of other, “dark” particles. But how do we look for these new particles? In this talk I advocate for the use of astrophysical objects as a laboratory to make progress on these puzzles. In particular, the referent will describe some ideas to use Supernovae and galaxy observations with line intensity mapping to shed some light on this darkness and probe motivated models such as axion-like particles, dark photons, light CP-even scalars. This effort is very timely, as it coincides with a broad set of astrophysical and cosmological observations becoming available now and in the near future.

11 Jan 2024

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

Institut für Physik

14:00 Uhr s.t., IPH Lorentzraum 05-127

Prof. Dr. Stefan Eriksson, Department of Physics, Faculty of Science and Engineering, Swansea University, UK
Precision measurements of the properties of trapped antihydrogen offer stringent tests of fundamental principles underlying particle physics and general relativity, such as Lorentz and CPT invariance and the Einstein Equivalence Principle. In this presentation I will give an overview of the ALPHA antihydrogen experiment at CERN including recent results from spectroscopy and observations of the effect of gravity. I will review how results are interpreted as tests of fundamental physics with a discussion of how a hypothetical CPT violation could result in matter-antimatter asymmetry. I will give an outline of the prospects for future high-precision spectroscopy, free-fall and gravitational redshift experiments with antihydrogen.

15 Jan 2024

Seminar about Experimental Particle and Astroparticle Physics (ETAP)

Institut für Physik

12:30 Uhr s.t., Staudingerweg 7, Minkowskiraum

Johann Martyn, Institut für Physik
Deployment of Water-based Liquid Scintillator in ANNIE
at https://indico.him.uni-mainz.de/event/199/

16 Jan 2024

Physikalisches Kolloquium

Institut für Kernphysik

16:15 Uhr s.t., HS KPH

Prof. Marco Durante, GSI Helmholtzzentrum für Schwerionenforschung GmbH
Particle therapy is a rapidly growing and potentially the most effective and precise radiotherapy technique. However, only a tiny minority of patients receive protons or heavy ions rather than X-rays these days. Physics research is needed to address a few problems that hamper its wider diffusion. The efforts are toward making particle therapy cheaper, faster, and more conformal. In this lecture we will give some examples of applications of nuclear physics to particle therapy. In particular, for reducing range uncertainty we will discuss the use of radioactive ion beams (RIBs) for simultaneous treatment and online range verification using positron emission tomography (PET) within the ERC AdG BARB (Biomedical Applications of Radioactive ion Beams) project at GSI/FAIR. We will also report on recent experiments in collaboration with Helmholtz Institute Mainz.
Slides here...

Seminar Festkörper- und Grenzflächenphysik KOMET - experimentell

Institut für Physik

12:00 Uhr s.t., Newton-Raum, Staudingerweg 9, 1. Stock, Raum 122 (Nebengebäude)

TBA, TBA
TBA

Theorie-Palaver

Institut für Physik

14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)

Álvaro Pastor Gutiérrez, MPIK Heidelberg
While the Standard Model of particle physics has been extremely successful in predicting experimental results, it still leaves us with unanswered questions about dark matter, the imbalance between matter and antimatter, and the emergence of fundamental scales. In this talk, I will outline our initial efforts to explore strong new physics scenarios using the non-perturbative functional renormalisation group. I will begin by introducing the flow equation and applying it to the Standard Model, thereby uncovering previously uncharted high-energy phases in the Higgs potential. The second part of the talk will focus on a comprehensive study of (quasi-)conformal “Technicolour” theories, aiming to identify Higgs-like bound states and detectable dark sectors. To achieve this, we will employ bosonisation techniques, which provide valuable insights into the properties of dynamically emergent bound states. I will conclude with a specific case study addressing the flavour puzzle within the framework of fundamental partial compositeness.

17 Jan 2024

PRISMA+ Colloquium

Institut für Physik

13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

Prof. Dr. Stephan Dolan, CERN, Switzerland
Accelerator-based neutrino oscillation experiments have the potential to revolutionise our understanding of fundamental physics, offering an opportunity to characterise charge-parity violation in the lepton section, to determine the neutrino mass ordering and to explore the possibility of physics beyond three-flavour neutrino mixing. However, as more data is collected the current and next-generation of experiments will require increasingly precise control over the systematic uncertainties within their analyses. It is well known that some of the most challenging uncertainties to overcome stem from our uncertain modelling of neutrino-nucleus interactions, arising because measured event rates depend on the neutrino interaction cross section in addition to any oscillation probability. The sources of these uncertainties are often related to subtle details of the pertinent nuclear physics, such as the details of the target nucleus ground state, which are extremely difficult to control with sufficient precision. Confronting such uncertainties requires both state-of-art theoretical modelling and precise measurements of neutrino interaction event rates at experiment's near detectors, before oscillations occur. In this talk, we review the role of neutrino interaction systematic uncertainties in current and future measurements of neutrino oscillations as well as the experimental and theoretical prospects for reducing them to an acceptable level for the next generation of experiments.

18 Jan 2024

GRK 2516 Soft Matter Seminar

Uni Mainz

14:30 Uhr s.t., Minkowski Room, 05-119, Staudingerweg 7

Sofia Kantorovich, Computational Physics, University of Vienna
TBA
at Zoom

Seminar über Theorie der kondensierten Materie / TRR146 Seminar

F. Schmid / G. Settanni / P. Virnau / L. Stelzl

14:30 Uhr s.t., Minkowski Room, 05-119, Staudingerweg 7

Sofia Kantorovich, Computational Physics, University of Vienna
GRK 2516 Soft Matter Seminar

23 Jan 2024

Physikalisches Kolloquium

Institut für Kernphysik

16:15 Uhr s.t., HS KPH

CANCELED: Prof. Jonathan Wurtele, University of Berkeley, California
This talk has been canceled due to illness! The ALPHA Collaboration at CERN synthesizes, traps, and investigates the properties of antihydrogen, the antimatter equivalent of hydrogen. ALPHA’s research has the goal of testing the standard model which holds that antihydrogen and hydrogen have the same spectrum, and the prediction of general relativity that antihydrogen atoms experience the same gravitational force as hydrogen atoms do. ALPHA’s experiments conducted over the last decade produced measurements of the 1S-2S line, hyperfine structure, Lyman-alpha transition, and charge neutrality of antihydrogen. This presentation will predominantly delve into our latest breakthrough. Utilizing an innovative magnet system, we have successfully observed, for the first time, the interaction of neutral antimatter with the Earth’s gravitational field. The best fit to our measurements yields a value of (0.75 ± 0.13 (stat. + syst.) ± 0.16 (simulation)) g for the local acceleration of antimatter towards the Earth, consistent with the predictions of general relativity. We rule out the possibility of antihydrogen experiencing an upwards acceleration g in the Earth’s gravity. Finally, potential paths to higher-precision gravity experiments will be discussed.

Seminar Festkörper- und Grenzflächenphysik KOMET - experimentell

Institut für Physik

12:00 Uhr s.t., Newton-Raum, Staudingerweg 9, 1. Stock, Raum 122 (Nebengebäude)

TBA, TBA
TBA

Theorie-Palaver

Institut für Physik

14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)

Daniel Schmitt, Frankfurt U.
Theories beyond the Standard Model (BSM) with classical scale invariance predict an intriguing thermal history of the early Universe. Due to the absence of dimensionful terms at tree level in these models, the electroweak phase transition (EWPT) can be significantly delayed, inducing a period of thermal inflation supercooling the Universe. The exit from this supercooled state can then be triggered via different mechanisms, depending on the model parameter space. In the first part of my talk, I will discuss the end of supercooling via a strong, first-order QCD chiral phase transition. I will outline how the associated gravitational wave (GW) production can be studied within effective QCD theories, with a particular focus on the effect of thermal inflation on the strongly coupled dynamics. In the second part, I will present an additional option to realize the exit from supercooling: a tachyonic phase transition. Here, the SM quark condensates source an exponential amplification of BSM scalar fields, generating a unique GW background detectable by future observatories.

24 Jan 2024

PRISMA+ Colloquium

Institut für Physik

13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

Prof. Dr. Kai Schmitz, Univ. Münster
Pulsar Timing Array (PTA) collaborations around the globe recently announced compelling evidence for low-frequency gravitational waves permeating our entire Universe, that is, a gravitational-wave background (GWB) reaching us from all directions and at all times. This breakthrough achievement has important implications for astrophysics, as the GWB signal, if genuine, is likely to originate from a cosmic population of supermassive black holes orbiting each other at the centers of galaxies. As the referent will illustrate in this talk, the new PTA data is, however, also of great interest to the high-energy physics community, as it allows to probe a broad range of particle physics models of the early Universe that predict the generation of a cosmological GWB in the Big Bang. In this sense, the PTA data opens a new window onto the very early Universe and enables particle physicists to constrain scenarios of new physics beyond the Standard Model at extremely high energies. In his talk, the referent will give an overview of these searches for new physics at the PTA frontier and highlight several cosmological scenarios that underline the relevance of PTA observations for fundamental problems such as dark matter, neutrino masses, and the matter-antimatter asymmetry of the Universe. Finally, he will conclude with a brief outlook on future measurements that may help in discriminating between a GWB signal of astrophysical origin and a GWB signal from the Big Bang.
Slides here...

25 Jan 2024

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

Institut für Physik

14:00 Uhr s.t., IPH Lorentzraum 05-127

Dr. Aleksandra Zoilkowska, JGU NEUQUAM Research Group
Cold atom experiments offer a distinctive platform for the investigation of many-body quantum physics, especially in non-equilibrium scenarios. The complexity inherent in these experiments often poses challenges to conventional theoretical methods. Nevertheless, exact analytical solutions become feasible when the underlying theory is integrable. Integrability plays a pivotal role in constraining the dynamics of many-body systems, enabling the derivation of, for instance, precise time-dependent density and velocity profiles after inhomogeneous quenches. This unique characteristic establishes a direct correspondence between theoretical predictions and experimental outcomes. In this talk, I will delve into the essence of quantum integrability and its efficacy in non-equilibrium many-body calculations, utilizing the framework of Generalized Hydrodynamics. An examination of the Lieb-Liniger Hamiltonian will exemplify how integrability has been applied in cold atom setups, resulting in the experimental realization of Quantum Newton's Cradle. Furthermore, I will draw upon my own research to provide insights into other quantum ''beasts'' emerging in out-of-equilibrium physics, rooted in an integrable theory known as the Homogeneous Sine-Gordon Model.

26 Jan 2024

Seminar über Theorie der kondensierten Materie / TRR146 Seminar

F. Schmid / G. Settanni / P. Virnau / L. Stelzl

10:15 Uhr s.t., Lorentz Room, 05-127, Staudingerweg 7

Scott Milner, Penn State University
Using simulations to predict miscibility

29 Jan 2024

Seminar about Experimental Particle and Astroparticle Physics (ETAP)

Institut für Physik

12:30 Uhr s.t., Staudingerweg 7, Minkowskiraum

Anamika Aggarwal, Institut für Physik
Phase-I Upgrade of the ATLAS Level-1 Calorimeter Trigger
at https://indico.him.uni-mainz.de/event/199/

30 Jan 2024

Physikalisches Kolloquium

Institut für Kernphysik

16:15 Uhr s.t., HS KPH

Prof. Silvia Masciocchi, Heidelberg/GSI
Very high energy densities are reached in ultra-relativistic collisions of heavy ions. Under these conditions, the confinement in strongly-interacting matter is lifted, and a quark-gluon plasma (QGP) is formed. At the highest temperatures realized in the laboratory, this system offers us the opportunity to study QCD matter under extreme conditions. The successful heavy-ion program at the LHC provides data of increasing precision. I will illustrate how experimental evidence supports the description of the QGP by fluid dynamics. This has been recently extended to include even rare and penetrating probes such as heavy quarks. Through this description and making use of neural networks and Bayesian inference, we are able to determine fundamental properties of QCD with increasing precision. A quick look into the formidable detectors with which we gain this evidence in the ALICE will complete the overview.
Slides here...

Seminar Festkörper- und Grenzflächenphysik KOMET - experimentell

Institut für Physik

12:00 Uhr s.t., Newton-Raum, Staudingerweg 9, 1. Stock, Raum 122 (Nebengebäude)

TBA, TBA
TBA

Theorie-Palaver

Institut für Physik

14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)

Maria Ramos, IFT Madrid
Singlet scalars, namely axion-like particles (ALPs), are among the most promising candidates of new physics. Standard (minimal) assumptions in the study of these particles might however hide a large landscape of solutions to different puzzles in the Standard Model, which can limit our discovery potential. In the first part of the talk, I will consider the impact of scalar mixing in the standard axion mechanism to solve the strong CP problem. I will show that the canonical axion mass-scale relation can be modified within QCD and multiple signals may be required to reconstruct the full solution to the strong CP problem, constrained by a precise sum rule. In the second part of the talk, I will discuss the impact of operator mixing, via RGEs, in the ALP parameter space. I will specially focus on shift-breaking and CP violating effects, and I will discuss some phenomenological applications.

31 Jan 2024

PRISMA+ Colloquium

Institut für Physik

13:00 Uhr s.t., MITP seminar room, Staudingerweg 9, 02-430

Noah Fleischer, LUB Mannheim
Mixed teams have greater collective knowledge, better ideas and fewer sick days. In short: more success. However, diverse teams also have different perspectives and are therefore more complex to manage. Professors often reach their limits with traditional management styles. This is because stereotypes relating to gender, age and social background persist and hinder equality. This leadership workshops deals with facts and figures on the topic of diversity & leadership in the university landscape - Anchoring diversity measures in daily university processes - Strategic leadership and teaching behavior using linguistic reframing techniques - Development of individually tailored measures for everyday life. Noah Fleischer combines his many years of experience in international management consulting in the corporate, political, and academic sectors with expertise as a university lecturer in advanced analytics and AI application development. He also advocates for the integration of diversity into the sustainability strategy and EU taxonomy. Noah Fleischer is also active as a mentor in the Friedrich Ebert Foundation and UN speaker on the topic of gender lens investing. All professors and group leaders are welcome. Please note that registration is required at prisma@uni-mainz.de until January, 10.

01 Feb 2024

GRK 2516 Soft Matter Seminar

Uni Mainz

17:00 Uhr s.t., TU Darmstad (Room, TBA)

Günter Auernhammer, Leibniz Institute for Polymer Research, Dresden
TBA
at Zoom

Seminar über Theorie der kondensierten Materie / TRR146 Seminar

F. Schmid / G. Settanni / P. Virnau / L. Stelzl

14:30 Uhr s.t., Minkowski Room, 05-119, Staudingerweg 7

Günter Auernhammer, Leibniz Institute for Polymer Research, Dresden
GRK 2516 Soft Matter Seminar

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

Institut für Physik

14:00 Uhr s.t., IPH Lorentzraum 05-127

Prof. Piet van Duppen, KU Leuven, Belgien
The thorium-229 nucleus contains an isomeric state with a low excitation energy, making it possible to probe using lasers. It is one of the best candidates for the development of a nuclear clock [1,2] which will enable the ability to test fundamental principles in physics (see e.g. [4]). However, to accomplish such a nuclear clock, the nuclear properties of the isomer need to be determined more precisely and two approaches are being followed. VUV spectroscopy revealed the radiative decay of the thorium-229 isomer in a study at ISOLDE-CERN by populating the isomer via the beta decay of actinium-229, implanting the beam in large bandgap crystals (CaF2 and MgF2). A reduced uncertainty of the isomer’s excitation energy (8.338±0.024 eV) and a first determination of the half-life (670±102 s) in MgF2 was reported [5]. During a follow-up campaign, different crystals were tested, the energy was determined with a better precision and the half-life behaviour of the VUV signal in the different crystals was studied. Preparatory work to perform laser ionization spectroscopy of the thorium-229 ground and isomeric states, populated in the alpha decay of uranium-233, is performed in an argon gas-jet based system. These studies, aimed to deduce the mean-square charge radii and moments of both ground and isomeric state, are based on singly charged thorium ions and necessitates a search for efficient and effective laser ionization schemes of thorium giving rise to a more precise determination of the first and second ionization potential. Results from these off and on-line studies will be presented and outlook to future work discussed. [1] E. Peik and C. Tamm, EPL 61, 181 (2003). [2] C. Campbell et al., Phys. Rev. Lett. 108, 120802 (2012). [3] L. von der Wense et al. Nature 533 (7601), 47–51 (2016). [4] E. Peik et al., Quantum Sci. Technol. 6, 034002 (2021). [5] Kraemer et al., Nature 617, 706–710 (2023).

Seminar über die Physik der kondensierten Materie (SFB/TRR173 Spin+X und SFB/TR288 Kolloquium, TopDyn-Seminar)

JGU

14:00 Uhr s.t., 01 122 Newton-Raum

Huaiyang YUAN, TU Delft and Zhejiang University
There is a rising interest in integrating magnetic systems with known quantum platforms for multi-functional quantum information processing. The coupling among magnons, photons, phonons, and qubits has already been proposed and demonstrated in the experiments. In this talk, I will introduce our recent results on the interplay of magnons and surface plasmons in two-dimensional systems. Our findings may open a novel route to integrate plasmonic and spintronic devices and bridge the fields of low-dimensional physics, plasmonics, and spintronics.

06 Feb 2024

Physikalisches Kolloquium

Institut für Kernphysik

16:15 Uhr s.t., HS KPH

Prof. J.C. Seamus Davis, University of Oxford
Everything around us, everything each of us has ever experienced, and virtually everything underpinning our technological society and economy is governed by quantum mechanics. Yet this most fundamental physical theory of nature often feels as if it is a set of somewhat eerie and counterintuitive ideas of no direct relevance to our lives. Why is this? One reason is that we cannot perceive the strangeness (and astonishing beauty) of the quantum mechanical phenomena all around us by using our own senses. I will describe the history of development of techniques that allow us to visualize electronic quantum phenomena and new states of quantum matter directly at the atomic scale. As recent examples, we will visually explore the previously unseen and very beautiful forms of quantum matter making up electronic liquid crystals[1,2], high temperature superconductors[2,3,4] and electron-pair crystals[5,6,7,8]. I will discuss the implications for fundamental physics research and also for advanced materials and new technologies, arising from quantum matter visualization. References: 1. Science 344, 612 (2014) 2. Nature 570, 484 (2019) 3. Science 357, 75 (2017) 4. Science 364, 976 (2019) 5. Nature 571, 234 (2020) 6. Nature 532, 343 (2016) 7. Science 372, 1447 (2021) 8. Nature 618, 921 (2023)
Slides here...

Seminar Festkörper- und Grenzflächenphysik KOMET - experimentell

Institut für Physik

12:00 Uhr s.t., Newton-Raum, Staudingerweg 9, 1. Stock, Raum 122 (Nebengebäude)

TBA, TBA
TBA

Theorie-Palaver

Institut für Physik

14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)

Filippo Sala, U. Bologna
I will show how first order phase transitions (PT) in the early universe, with relativistic bubble walls, constitute particle accelerators and colliders via the dense shell of particles that they necessarily accumulate. These `bubbletrons' offer novel opportunities of observational access to very high energy scales, in addition to the gravitational waves from the PT. As three examples, I will discuss: i) non-adiabatic production of ZeV dark matter which is hot enough to leave an imprint in the matter power spectrum; ii) production of relics beyond the GUT scale without the need for the universe to ever reach those temperatures; iii) realization of testable baryogenesis and leptogenesis down to the TeV scale. In passing I will mention open questions about the physics of particle shells at bubble walls, and their potential far-reaching implications.

07 Feb 2024

PRISMA+ Colloquium

Institut für Physik

13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

Prof. Dr. Martin Fertl, JGU Mainz, Institut für Physik, QUANTUM
Please see attachment
Slides here...

08 Feb 2024

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

Institut für Physik

14:00 Uhr s.t., IPH Lorentzraum 05-127

Prof. J.C. Séamus Davis, University of Oxford, Oxford, UK
Although UTe2 appears to be the first 3D spin-triplet topological superconductor, its superconductive order-parameter Δ_k has not yet been established. If spin-triplet, it should have odd parity so that Δ_(-k)=-Δ_k and, in addition, may break time-reversal symmetry. A distinctive identifier of 3D spin-triplet topological superconductors is the appearance of an Andreev bound state (ABS) on all surfaces parallel to a nodal axis, due to the presence of a topological surface band (TSB). Moreover, theory shows that specific ABS characteristics observable in tunneling to an s-wave superconductor distinguish between chiral and non-chiral Δ_k. To search for such phenomena in UTe2 we employ s-wave superconductive scan-tip imaging of UTe2 [1] to discover a powerful zero-energy ABS signature at the (0-11) crystal termination [2]. Its imaging yields quasiparticle scattering interference signatures of two Δ_k nodes aligned with the crystal a-axis. Most critically, development of the zero-energy Andreev conductance peak into two finite-energy particle-hole symmetric conductance maxima as the tunnel barrier is reduced, signifies that UTe2 superconductivity is non-chiral. Overall, the discovery of a TSB, of its a zero-energy ABS, of internodal scattering along the a-axis, and of splitting the zero-energy Andreev conductance maximum due to s-wave proximity, categorizes the superconductive Δ_k as the odd-parity non-chiral B3u state [2], which is equivalent to the planar state of superfluid 3He. [1] Nature 618, 921 (2023) [3] Gu, Wang, et al. Science (2023)