# Semesterübersicht – letztes Semester

## Semesterübersicht Wintersemester 2021/2022

13 Oct 2021

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t.
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.
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.
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.
 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.
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.
 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.
 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.
 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.
 Natalie Klco, Caltech please note different time! at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t.
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.
 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.
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.
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.
 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.
 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.
 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.
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.
Emma Rossi, University of Padua, Italy
at Zoom

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

###### Institut für Physik14:00 Uhr s.t.
 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.
 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.
Martin Hoferichter, Universität Bern
at Zoom

25 Nov 2021

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

###### Institut für Physik14:00 Uhr s.t.
 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.
 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.
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.
 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.
 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.
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.
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.
 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.
 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.
 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.
Patrick Owen, Universität Zürich
at Zoom

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t.
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.
 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
03 Jan 2022

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

###### Institut für Physik12:30 Uhr s.t., only at Zoom
Francesco Lombardi, Institut für Physik

04 Jan 2022

### Physikalisches Kolloquium

###### Institut für Kernphysik16 Uhr c.t., Hörsaal CO2 Chemie - Nord-Ost (2321) Duesbergweg 10 - 14
Dr. Dionysis Antipas, University of Mainz

06 Jan 2022

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

###### Institut für Physik14:00 Uhr s.t.
 Prof. Stefan Willitsch, Universität Basel The development of quantum technologies for molecules has remained a long-standing challenge due to the complexity of molecular systems. We have recently developed a quantum-non-demolition technique for the non-destructive detection of the internal quantum state of a single trapped molecular ion [1,2,3]. The method is based on the state-dependent coherent excitation of the motion of the molecular ion and subsequent measurement of the motional quantum state using a co-trapped atomic ion. This approach offers new perspectives not only for the detection, but also for the preparation and the manipulation of molecular quantum states on the single-particle level with a sensitivity several orders of magnitude higher compared to previously used destructive schemes. We present a characterisation of the technique using the homonuclear diatomic ion N2+ as an example and show how it can be used for non-invasive spectroscopic measurements on single molecules. We also discuss applications of this technique in the realm of precision molecular spectroscopy [4] using a newly established fibre network for the precise transfer of frequencies within Switzerland and their comparison to the Swiss primary standard at METAS. References: [1] Z. Meir, G. Hegi, K. Najafian, M. Sinhal and S. Willitsch, "State-selective coherent motional excitation as a new approach for the manipulation, spectroscopy and state-to-state chemistry of single molecular ions”, Faraday Discuss. 217 (2019), 561. [2] M. Sinhal, Z. Meir, K. Najafian, G. Hegi and S. Willitsch, "Quantum non-demolition state detection and spectroscopy of single trapped molecules”, Science 367 (2020), 1213. [3] K. Najafian, Z. Meir, M. Sinhal and S. Willitsch, "Identification of molecular quantum states using phase-sensitive forces”, Nat. Commun. 11 (2020), 4470. [4] K. Najafian, Z. Meir and S. Willitsch, ”From megahertz to terahertz qubits encoded in molecular ions: theoretical analysis of dipole-forbidden spectroscopic transitions in N2+”, Phys. Chem. Chem. Phys. 22 (2020), 23083. [5] D. Husmann et al., “SI-traceable frequency dissemination at 1572.06 nm in a stabilized fiber network with ring topology”, Opt. Expr. 29 (2021), 24592. at Zoom
10 Jan 2022

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

###### Institut für Physik12:30 Uhr s.t., only at Zoom
Daniel Wenz, Institut für Physik

11 Jan 2022

### Physikalisches Kolloquium

###### Institut für Kernphysik16:15 Uhr s.t., Hörsaal CO2 Chemie - Nord-Ost (2321) Duesbergweg 10 - 14
 Hans-Jürgen Butt, MPI für Polymerforschung Physics near a contact line is the key to understanding dynamic wetting. We encounter wetting processes all the time in everyday life - typical applications include coating, printing, spreading herbicides and insecticides, and fogging. They also occur in the enrichment of minerals by flotation and in soldering and lubrication, as well as in the wetting of textiles and filters. Nevertheless, dynamic wetting is poorly understood, both qualitatively and quantitatively. To better understand these processes, it is necessary to consider the physics near the contact line where liquid, solid and gas meetSlides here...
12 Jan 2022

### PRISMA+ Colloquium

###### Institut für Physik13:00 Uhr s.t.
Liu Hanjie, University of Massachusetts
at Zoom

### Theorie-Palaver

###### Institut für Physik14:30 Uhr s.t.
 Bianca Dittrich, Perimeter Institute There is more and more evidence that quantum gravity should be rather defined from the Lorentzian path integral than the Euclidean one. But there are many open questions concerning the Lorentzian path integral. Two of these are: Which configurations should be included in the Lorentzian path integral, e.g. should we include configurations that violate causality conditions? And how to compute the Lorentzian path integral? Using Picard-Lefshetz theory to compute the Lorentzian path integral for Regge gravity, I will explain how this method can also inform on the first question. This example indicates that we can allow for causality violations to occur, but that the corresponding amplitudes are suppressed by the dynamics. at Zoom
13 Jan 2022

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

###### Institut für Physik14:00 Uhr s.t.
 Prof. James Thompson, JILA; University of Colorado, Dept. of Physics, Boulder/USA I will discuss a range of cavity QED experiments that explore how to exploit atom-light interactions to create atom-atom correlations and entanglement for quantum sensing and quantum simulation. Using rubidium atoms, we have implemented both cavity-enhanced quantum nondemolition measurements and cavity-mediated spin-spin interactions to realize an entangled light-pulse matterwave interferometer that is directly observed to operate below the standard quantum limit [1]. Using strontium atoms, we have achieved pulsed superradiant lasing on the millihertz clock transition [2,3], developed a new method for determining the intrinsic radiative lifetime of the clock state [4], and observed a dynamical phase transition [5] arising from a competition between cavity-mediated spin exchange interactions [6] and single particle dynamics. If time permits, I will briefly describe our progress toward a continuous superradiant laser. [1] Greve & Luo et al, arXiv:2110.14027 (2021) [2] Norcia et al, Science Adv. 2 e1601231 (2016) [3] Norcia et al, Phys. Rev. X 8 021036 (2018) [4] Muniz et al, Phys. Rev. Res. 3 023152 (2021) [5] Muniz et al, Nature 580 602 (2020) [6] Norcia et al, Science 361 259 (2018) at Zoom
17 Jan 2022

### 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
Jayasimah Atulasimha, Virginia Commonwealth University
at Zoom

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

###### Institut für Physik12:30 Uhr s.t., only at Zoom
Alfons Weber, Institut für Physik

18 Jan 2022

### Theorie-Palaver

###### Institut für Physik14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)
 Anne Mareike Galda, JGU Mainz The Standard Model Effective Field Theory (SMEFT) provides a systematic framework to parametrize the low-energy effects of unknown heavy particles. In this talk, I will show that in the presence of additional light particles such as axions and ALPs coupled to the Standard Model (SM) via classically shift-invariant dimension-5 operators, SMEFT Wilson coefficients are generated by means of one-loop order renormalization group (RG) evolution equations. This yields additional contributions to low-energy observables which I will discuss for the case of the top chromo-magnetic dipole moment to lowest logarithmic order.Slides here... at Zoom

### Physikalisches Kolloquium

###### Institut für Kernphysik16 Uhr c.t.
 Marek Kowalski, HU Berlin/DESY During the last years we have witnessed several breakthroughs in the field of astroparticle physics and astronomy, ranging from the detection of optical counterparts of the gravitational wave sources to the first likely identification of a source of high-energy cosmic neutrinos – a bright gamma-ray Blazar. And most recently, we have traced back a high-energy neutrino detected by IceCube to a Tidal-Disruption Event, providing first evidence that these objects might be the sights of extreme particle acceleration. All these observations have in common that they capture transient phenomena, with multi-messenger follow-up observations required to be performed in near realtime. In my talk I will discuss the technological challenges of the field, our solutions as well as what we have learned about the sources of cosmic neutrinos neutrino from our new observations. I will also present future projects that promise to become game changers for the field of high-energy multimessenger astronomy. at Zoom
19 Jan 2022

### PRISMA+ Colloquium

###### Institut für Physik13:00 Uhr s.t.
 Francesca Carlin, Coach, Berlin Special event! Picture a Scientist: Do you fit the image? Defining and Redefining the Role Online talk and discussion about how gender and implicit biases affect scientific careers with Francesca Carlin, Coach at Zoom

### SPICE-Spin+X Seminar

##### Theory of magnetic interactions in real materials
at Zoom and SPICE YouTube Channel

20 Jan 2022

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

###### Institut für Physik14:00 Uhr s.t.
 Prof. Ania Bleszynski Jayich, University of California, Physics Dept., Santa Barbara/USA Solid state spin qubits, in particular the nitrogen vacancy (NV) center in diamond, offer a path towards truly nanoscale imaging of condensed matter and biological systems with sensitivity to single nuclear spins. Here I discuss our NV-based magnetic imaging experiments as applied to condensed matter systems, where we have imaged current flow patterns in graphene as well as skyrmions, nanoscale spin textures. A grand challenge to improving the spatial resolution and magnetic sensitivity of the NV is mitigating surface-induced quantum decoherence, which I will discuss in the second part of this talk. Decoherence at interfaces is a universal problem that affects many quantum technologies, but the microscopic origins are as yet unclear. Our studies guide the ongoing development of quantum control and materials control, pushing towards the ultimate goal of NV-based single nuclear spin imaging. at Zoom

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:15 Uhr s.t.
 M. Schweitzer, JGU, Chemistry Synthetic hydrogels have sparked high interest in recent years as matrix materials for biotechnological applications. In supramolecular hydrogels the three-dimensional gel network is formed by non-covalent interactions between small molecules. These can be influenced and selectively switched on and off by external stimuli. Telechelic polymer-peptide conjugates using the basic amino acid histidine in a hydrophobic phenylalanine (F)-histidine (H) pentapeptide sequence FHFHF have previously been reported to promote pH-switchable self-assembly into one-dimensional nanorods by β-sheet formation. When encoding for assembly into parallel β-sheets these structures have also shown interstrand cross-linking, leading to the formation of hydrogels. Furthermore, ROS-responsiveness can be achieved by altering the peptide sequence to incorporate methionine. The use of polymer-peptide conjugates combines the advantages of synthetic polymers like the easy scalability with the defined amino acid sequence and the resulting high structural definition of peptides. In this work we report the synthesis of telechelic poly(ethylene glycol)-peptide conjugates and their ability to form multistimuli-responsive hydrogels. The terminal peptide blocks contain the hydrophobic pentapeptide sequence FHFHF to promote pH-switchable β-sheet formation and self-assembly into nanorods as well as interstrand cross-linking for hydrogelation. The conjugates were characterized by NMR and GPC and the pH-switchable self-assembly and formation of nanorods was confirmed via CD-spectroscopy and transmission electron microscopy. Rheological measurements of hydrogels at physiologically relevant conditions showed responsiveness to pH-value and temperature. at Zoom

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:45 Uhr s.t.
 Philipp Ritzert, TU Darmstadt, Physics The fabrication of composite materials from inorganic nanoparticles (NPs) and an organic matrix significantly enriched the field of nanotechnology as components facilitate each other or cover a significant drawback. Thereby, the blending of components enables various novel application, e.g. for catalysis, nano-sensors, and medical engineering. Despite the numerous improvements over the last years, the assembly of small NPs within a polymer matrix is still not well understood. To overcome the resulting limit of accessible structures, we pursue a more controlled approach of NP formation inside a polymer matrix, utilising gold NPs as model system. During NP self-assembly, specific stimuli (represented by five Na salts of varying concentration) assert control over the NP structure by guiding the system through a series of kinetically trapped states. Prior to investigation of NP assemblies in a polymer matrix, the response of gold NPs suspensions needs to be well characterised. Therefore, suspensions of gold NPs (∼10nm) with two capping agents are mixed with different Na-salts along the Hofmeister series (anion: F, Cl, Br, I, SCN), and optically monitored by a camera and a spectrometer. The aggregation and sedimentation behaviour reveals non-systematic ion- specific effects, which further depend on the NP size and capping agent. at Zoom
24 Jan 2022

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

###### Institut für Physik12:30 Uhr s.t., only at Zoom
Alexander Basan, Institut für Physik

25 Jan 2022

### Physikalisches Kolloquium

###### Institut für Kernphysik16 Uhr c.t., Hörsaal CO2 Chemie - Nord-Ost (2321) Duesbergweg 10 - 14
Mikhail Eremets, MPIC Mainz

### Theorie-Palaver

###### Institut für Physik14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)
 Aqeel Ahmed, Max Planck Institute Heidelberg We present a class of models in which dark matter is composed of the composite states of a strongly coupled hidden sector. The hidden sector interacts with the standard model through the neutrino portal, allowing the relic abundance of dark matter to be set by annihilation into final states containing neutrinos. The coupling to the hidden sector also leads to the generation of neutrino masses through the inverse seesaw mechanism, with composite hidden sector states playing the role of the singlet neutrinos. We focus on the scenario in which the hidden sector is conformal in the ultraviolet, and the compositeness scale lies at or below the weak scale. We construct a holographic realization of this framework based on a five-dimensional warped geometry and study its phenomenology. at Zoom
26 Jan 2022

### PRISMA+ Colloquium

###### Institut für Physik13:00 Uhr s.t.
Maarten Boonekamp, Saclay / HIM
at Zoom

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

###### K. Binder/ A. Nikoubashman / F. Schmid / G. Settanni / T. Speck / M. Sulpizi / P. Virnau15:30 Uhr s.t.
Ann-Katrin Fattal and Christopher Schierholz, Continental
at Teams

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t.
Caroline A. Ross, Massachusetts Institute of Technology
##### Iron garnet thin films for spintronic and photonic devices
at Zoom and SPICE YouTube Channel

27 Jan 2022

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

###### Institut für Physik14:00 Uhr s.t.
 Dr. Sandra Eibenberger-Arias, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin Chiral molecules are ubiquitous in nature and they are of great importance in many biological and chemical processes. They are also at the center of some interesting fundamental physics questions, for example whether there is parity violation in chiral molecules, which has been long predicted but never experimentally observed. In my presentation I will discuss important recent experimental developments targeted at the understanding and the control of cold, chiral molecules in the gas phase. I will show the microwave three-wave mixing technique where the enantiomers of a chiral molecule can be distinguished in a sensitive, non-destructive way [1]. I will also discuss enantiomer-specific population transfer, an all-coherent method to populate a chosen rotational state preferentially with one enantiomer [2]. I will further discuss recent progress in my lab in Berlin [3], where we realize increased control of chiral molecules by employing high resolution spectroscopy techniques in the UV and microwave regime [4]. [1] D. Patterson, M. Schnell, and J. Doyle, Nature 497, 475 (2013) [2] S. Eibenberger, J. Doyle, D. Patterson, Phys. Rev. Lett. 118, 123002 (2017) [3] A. O. Hernandez-Castillo, J. Bischoﬀ, J. H. Lee, J. Langenhan, M. Karra, G. Meijer, and S. Eibenberger-Arias, Phys. Chem. Chem. Phys. (2021) [4] J. H. Lee, J. Bischoff, A. O. Hernandez-Castillo, B. Sartakov, G. Meijer, and S. Eibenberger-Arias, in preparation (2021) at Zoom

### 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.
Joshua Robinson, Department of Physics, Uni Mainz
at Zoom

31 Jan 2022

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

###### Institut für Physik12:30 Uhr s.t., only at Zoom
Sebastian Ritter, Institut für Physik

01 Feb 2022

### Physikalisches Kolloquium

###### Institut für KernphysikSonderseminar: 16 Uhr c.t., via Zoom
Julie Grollier, CNRS/Thales Lab
##### Neuronale Netze / Festkörper

Sonderseminar

The lecture is CANCELLED

### Theorie-Palaver

###### Institut für Physik14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)
 Rachel Houtz, Durham U. and IPPP In this talk, I present a simple method to identify a continuous Lie group symmetry in a data set through regression by an artificial neural network. The proposal takes advantages of the order \epsilon^2 scaling under infinitesimal symmetry transformations. The main advantages of this methodology are that it does not rely on binning of the data set and no assumptions about the symmetry need to be made. The method is demonstrated in the SU(3)-symmetric (non-) linear sigma model. at Zoom
02 Feb 2022

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t.
Amalio Fernández-Pacheco, CSIC-University of Zaragoza
##### Three dimensional spintronics: “Faster, higher, stronger"
at Zoom and SPICE YouTube Channel

03 Feb 2022

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

###### Institut für Physik14:00 Uhr s.t.
 Prof. Ronald Fernando Garcia Ruiz, Massachusetts Institute of Technology (MIT), Cambridge, MA/USA Molecules containing heavy and octupole deformed radioactive nuclei are predicted to provide enhanced sensitivity to investigate distinct nuclear phenomena, to test the violation of fundamental symmetries, and to search for new physics beyond the Standard Model of particle physics. However, experimental measurements of such radioactive systems are scarce, and their study requires to overcome major experimental challenges. This seminar will discuss recent spectroscopy measurements of short-lived radium fluoride molecules (RaF) alongside future perspectives in the study of these and other radioactive molecules. at Zoom

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:15 Uhr s.t.
 Oliver Stach, JGU, Chemistry We report the sequential growth of supramolecular copolymers on gold surfaces, using oppositely charged dendritic peptide amphiphiles. By including water-solubilizing thermoresponsive chains in the monomer design, we observed non-linear effects in the temperature-dependent sequential growth. The step-wise copolymerization process is characterized using temperature dependent SPR and QCM-D measurements. At higher temperatures, dehydration of peripheral oligoethylene glycol chains supports copolymer growth due to more favorable comonomer interactions. Both monomers incorporate methionine amino acids but remarkably, desorption of the copolymers via competing Sulphur gold interactions with the initial monomer layer is not observed. The surface-confined supramolecular copolymers remain kinetically trapped on the metal surface at near neutral pH and form viscoelastic films with a tunable thickness. at Zoom

### GRK 2516 Soft Matter Seminar

###### Uni Mainz10:45 Uhr s.t.
 Yashraj Manish Wani, JGU, Physics Understanding the dynamics of colloidal suspensions is essential for prediction and engineering of micro-structures that have several technical applications. Owing to the complexity of particle interactions, numerical techniques are well suited for studying such systems. We are interested in studying colloid dynamics using mesoscale computer simulations, focusing on a recently proposed approach based on multi-particle collision dynamics. A major benefit of this approach is that it allows us to simulate colloidal particles with complex geometries. We have studied the equilibrium and sedimentation dynamics of spherical particles in suspensions with varying concentrations. Compared with other theoretical and experimental studies, we found some anomalies with the short-time equilibrium dynamics, but the long-time equilibrium dynamics and sedimentation dynamics are consistent with the presence of appropriate hydrodynamic interactions. To demonstrate the extensibility of the approach, we study the equilibrium dynamics of cubic colloidal particles. at Zoom
07 Feb 2022

### 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
 Mario Carpentieri, Politecnico di Bari (Italy) Zoom ID: 641 9279 3075 Passcode: 4Ko!!2122Slides here... at Zoom
08 Feb 2022

### Theorie-Palaver

###### Institut für Physik14:00 Uhr s.t., Lorentz room (Staudingerweg 7, 5th floor)
 Toby Opferkuch, UC Berkeley and LBNL Neutrino emission plays an important role in the cooling of neutron stars. Thermally emitted neutrinos, however, have sub-MeV energies and are therefore all but impossible to detect from such distant sources. In this talk I will argue that neutron stars should emit a secondary, non-thermal, neutrino flux arising from out-of-equilibrium muon decays. Muons are abundant in the core of the star, but due to the large electron chemical potential, their decay is initially prevented by Pauli blocking. Over timescales of order years, however, they can diffuse outwards into regions of low electron chemical potential, where their decay becomes possible and results in a flux of neutrinos with energies up to 40 MeV. While detecting this flux from a single neutron star is challenging, the integrated flux from all neutron stars in the Milky Way is comparable to the diffuse supernova neutrino background, it may be observable in next-generation detectors like DUNE and HyperKamiokande. This would offer a unique new way of probing the inner structure of neutron stars. at Zoom
09 Feb 2022

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t.
Yuriy Mokrousov, JGU
##### Detecting, imprinting and switching spin chirality in magnetic materials
at Zoom and SPICE YouTube Channel

16 Feb 2022

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t.
Mathias Weiler, TUK
##### Magneto-Acoustic Waves in Magnetic Thin Films
at Zoom and SPICE YouTube Channel

at Zoom

MPI Seminar

21 Feb 2022

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

Jamie Boyd, CERN
##### Forward Physics Facility
at Zoom also available

23 Feb 2022

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t.
Tiffany Santos, Western Digital Corporation, USA
##### Spins, Bits, and Flips: Essentials for High-Density Magnetic Random-Access Memory
at Zoom and SPICE YouTube Channel

30 Mar 2022

### SPICE-Spin+X Seminar

###### TUK and JGU15:00 Uhr s.t.
Christian Tzschaschel, Harvard University
##### Ultrafast optical excitation and probing of coherent antiferromagnetic spin dynamics
at Zoom and SPICE YouTube Channel