News

Magnetic order traps quasi-1D excitons

© Brad Baxley, PtW

We explored how the antiferromagnetic spin alignment in adjacent layers of the van der Waals crystal CrSBr confines Coulomb bound electron hole pairs into one dimension. In two back-to-back publications in Nature Materials, we discovered two key signatures of this intriguing process: In a close collaboration with the groups of Mackillo Kira (University of Michigan), Zdeněk Sofer (University of Chemistry and Technology Prague) and Florian Dirnberger (Technical University of Munich), we resolved the internal structure and a strong fine-structure splitting of the excitons.

Visualizing ultrafast electron wave motion in graphene: Coverstory in Nano Letters

© Simon Anglhuber, UR

We explored a novel approach to directly visualize THz surface polariton propagation in both space and time – accessing the polariton’s group and phase velocities, as well as its damping. Through photoexcitation, we even achieved subcycle control of the polariton propagation.

The results obtained in close collaboration with the group of Miriam Vitiello in Pisa (NEST, CNR) and Eva A. A. Pogna in Milano (CNR-IFN) have been published in Nano Letters (Coverstory).

Unlocking Lightwave Electronics

Our review on lightwave electronics together with Mackillo Kira has made it on the cover of Optics & Photonics News. © S. Alvey, University of Michigan

Joshua Mornhinweg receives the dissertation prize of the faculty of physics!

We congratulate Joshua Mornhinweg on being awarded the Dissertation Prize by the Faculty of Physics at the University of Regensburg for his remarkable PhD thesis, titled "Tailoring and Non-Adiabatic Control of Deep-Strong Light-Matter Coupling." This prize, sponsored by the Wilhelm and Else Heraeus Foundation, recognizes an exceptional doctoral thesis in physics and comes with an endowment of €4000.

Josef Riepl receives the Best Tutor Award of the faculty of physics

We are happy to announce that Josef Riepl won the Best Tutor Award of the Faculty of Physics at the University of Regensburg. The price recognizes his outstanding job in teaching and explaining the physics of electrodynamics. Congratulations, Josef!

Vertical voyage in metal halide perovskites

© Brad Baxley, PtW

We have developed an approach based on ultrafast near-field microscopy that has allowed us to probe the nanoscale topography, crystallographic phase and chemical composition of metal halide perovskite films, while simultaneously extracting the ultrafast vertical carrier dynamics from femtosecond shifts in the pump-induced response following photoexcitation. This has revealed a surprising robustness of vertical charge transport towards nanoscale structural and compositional variations.

The results obtained in a close collaboration with the group of Michael Johnston (University of Oxford) have appeared in Nature Photonics.

Felix Schiegl receives QMSL 2024 best oral presentation award

We congratulate Felix Schiegl on winning the best oral presentation award of the 2024 International workshop Quantum Materials and Structured Light (QMSL) in Erice with his talk titled "All-Optical Subcycle Microscopy of Quantum Materials at the Atomic Scale". The prize honours original contributions to the conference from outstanding student attendees.

Atomic-scale telegraphy with light

© Brad Baxley, PtW

We have discovered an entirely unforeseen quantum-mechanical contrast mechanism that finally enables all-optical microscopy to achieve atomic resolution while retaining subcycle temporal precision. This new concept allows us to directly trace the quantum flow of electrons on their intrinsic length and time scales.

The results obtained in a close collaboration with the group of Jan Wilhelm (University of Regensburg) have appeared in Nature.

Quantum dance to the beat of a drum: Coverstory in Nature Photonics

© Brad Baxley, PtW

We have established ultrafast scanning tunnelling spectroscopy on the femtosecond time, atomic length and milli-electron-volt energy scale. This has allowed us to directly resolve the energy shift of a single atomic defect in a monolayer of tungsten diselenide due to drum-like phonon vibrations.

The results obtained in a close collaboration with the groups of Jascha Repp (University of Regensburg) and Jan Wilhelm (University of Regensburg) have appeared in Nature Photonics.

Mode-multiplexing deep-strong light-matter coupling

In close collaboration with the groups of Dominique Bougeard (UR) and Christoph Lange (TU Dortmund), we were able to reach record-breaking, deep-strong light-matter coupling with a coupling strength of up to 3.19. This, for the first time, creates vacuum ground state populations exceeding 1 virtual excitation quantum.

The results have been published in Nature Communications.

Best Lecture Award

Our lecture on Light Matter Interaction was awarded with the Best Lecture Award of the Faculty of Physics. Image (from left to right): Manuel Meierhofer, Rupert Huber, Simon Maier, Marlene Liebich
Missing: Markus Huber

Feodor Lynen Research Fellowship for Joshua Mornhinweg

Congratulations to Joshua Mornhinweg for being awarded the prestigious “Feodor Lynen Research Fellowship” from the Alexander von Humboldt Foundation! The fellowship recognizes Joshua’s outstanding scientific work on deep-strong light-matter coupling and will allow Joshua to join the group of Prof. Federico Capasso at Harvard University to work on novel “polaritonic and superconducting reconfigurable THz metasurfaces”.

Graduate Research Training Group 2905 funded

© Brad Baxley, PtW

The new Graduate Research Training Group 2905 - "Ultrafast nanoscopy - from single particle dynamics to cooperative processes" - will be funded for five years.

The program will start April 2024 and allows graduate researchers to unveil the internal dynamics of the elementary building blocks of matter. Novel concepts of nanovideography will be pioneered to resolve atomic-scale dynamics and to trace ensuing cooperative processes in systems of increasing complexity directly in ultraslow-motion pictures. The discoveries could find applications in future nano- and optoelectronics, quantum technologies and green technologies.

Press release (UR) in German and English.
Press release (idw) in German and English.

Josef Freudenstein receives IRMMW-THz 2023 best student presentation award

We congratulate Josef Freudenstein on winning the first prize of the best student presentation award of the 2023 International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) in Montréal. The prize honours original contributions to the conference from outstanding student attendees and was awarded for his talk titled “Attoclocking delocalized Bloch electrons with multi-terahertz fields".

Our latest review on lightwave electronics in condensed matter has appeared

In collaboration with Mackillo Kira and Markus Borsch from the University of Michigan, we have reviewed the field of lightwave electronics ranging from high-harmonic generation to subcycle imaging concepts. The review has been published in Nature Reviews Materials.