Programm Sommersemester 2023

Montag, 03.07.2023, 16:30 Uhr Physik Hörsaal

Prof. Dr. Mario Berta (RWTH Aachen University)

Quantum Algorithm Development



Information technologies based on components governed by the laws of quantum physics have long promised a transformative impact on computing. Most famously, this includes quantum computers running dramatically faster algorithms than those available for computers based on classical physics. In my talk, I will discuss the current state of quantum hardware and present a critical assessment of the landscape of quantum algorithms from an application driven perspective. Looking forward—and as improvements in quantum hardware increase the number and quality of qubits—we seek quantum algorithms that are able to showcase practical quantum advantage against state-of-the-art classical methods. Towards this goal and motivated by applications in scientific computing for condensed matter physics and computational chemistry, I will present a selection of our recently developed qubit efficient, hybrid quantum algorithms. These allow for a flexible trading between quantum circuit depth and sample complexity — while outsourcing all but the critical quantum sub-routines to classical pre- and post-processing.



Host: Hendrik Bluhm





Montag, 26.06.2023, 16:30 Uhr Physik Hörsaal

Prof. Marc Schumann (Universität Freiburg)

Exploring the Dark Universe



Ample of indirect evidence indicates that the vast majority of the matter in the Universe is dark and neither emits nor absorbs light. The existence of this dark matter is one of the strongest hints that our current understanding of the fundamental constituents of the Universe is incomplete, as no known particle has the right properties. We will discuss the evidence for dark matter and the experimental approaches to directly detect the dark matter particles in our galactic neighborhood. These searches are currently led by large low-background detectors using cryogenic liquid xenon as dark matter target. As these instruments get larger and achieve better and better background levels, the sensitivity to dark matter particles increases and additional science channels become accessible.


Host: Christopher Wiebusch




Montag, 05.06.2023, 16:30 Uhr Physik Hörsaal

Dr. David Dahmen ( Jülich Research Centre)

Disordered-systems and field-theoretic approach to heterogeneous neural networks



Neural networks in the brain and in machine learning are disordered systems of many interacting nonlinear units. In biological networks one predominant form of disorder is the sparse and heterogeneous local connectivity between neurons; in artificial networks it is the random initialization of couplings before training on a specific task. While the amount of randomness in both systems has been linked to critical behavior and computational performance, a full understanding of the dynamical and functional consequences is currently still lacking. In this talk, I demonstrate how to use field-theoretic tools from statistical physics of spin glasses to obtain predictions for spatio-temporal correlation patterns, the hallmarks of collective behavior and function in biological and artificial neural networks, and compare these predictions to electrophysiological recordings of parallel neural activity in the brain.


Host: Michael Kraemer





Montag, 22.05.2023, 16:30 Uhr Physik Hörsaal

Prof. Dr. Hans-Walter Rix (MPI for Astronomy Heidelberg)

Where do black holes in the Universe come from?



Over the last 50 years the existence of black holes has been established by different

astrophysical means: the dynamics of stars and gas, emission from accretion disks 

surrounding them and gravitational waves. Black holes appear to exist over a vast range 

masses, from a few times the mass of the Sun to a few billion Solar masses. But in many

circumstances black holes have remained undetectable by current detection efforts, and 

we may just see the tip of the population iceberg. I’ll discuss some of the ongoing and

upcoming efforts (including our own) to detect new parts of the black hole population. And

I’ll sketch what this implies for their origin: When do massive stars leave black holes behind?

Do all black holes in the Universe ultimately trace back to stellar remnants? 

And, can black holes be a significant part of dark matter?


Host: Oliver Pooth





Montag, 08.05.2023, 16:30 Uhr Physik Hörsaal

Dr. Axel Lindner (DESY)

Axion searches at DESY: starting now!



The worldwide interest in axions and other weakly interacting slim particles (WISPs) as constituents of a dark sector of nature has strongly increased over the last years. A vibrant community is developing, constructing and operating corresponding experiments, so that promising parameter regions will be probed within the next 15 years.

Many of these approaches rely on WISPs converting to photons. At DESY in Hamburg, larger-scale projects are pursued: the “light-shining-through-a-wall” experiment, ALPS II in the HERA tunnel, is about to start data taking. The solar helioscope BabyIAXO is nearly ready to start construction, while the dark matter haloscope MADMAX is in the prototyping phase.

This presentation will introduce the physics cases and focus on the axion search activities ongoing at DESY in Hamburg.


Host: Lutz Feld




Friday 28th April 2023, 4pm Physics lecture hall

Symposium on the occasion of the 80th birthday of Prof. Gernot Güntherodt




16:05 – 16:15    Opening 


16:15 – 16:30    Ulrich Rüdiger (Rector of the RWTH Aachen University)

                          Welcome address


16:30 – 16:50    Stuart Parkin (Max Planck Institute of Microstructure Physics, Halle (Saale))   

                           Memory on the racetrack


16:50 – 17:10    Werner Hanke (University of Würzburg)

                          Room-temperature excitons in a topological insulator


17:30 – 17:50    Burkard Hillebrands (TU Kaiserslautern)

                           Spin waves and magnonics   


17:50 – 18:10    Ioana Slabu (Institute of Applied Medical Engineering, RWTH Aachen Univ.)

                          Precision Medicine with Magnetic Nanomaterials


18:10 – 18:30    Dieter Vollhardt (University of Augsburg)

                          Theories in the Natural Sciences


18:30 – 18:40    Conclusion


The symposium will take place in the Physics lecture hall (28D 001).