2025-02-19
© 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. |
We also contributed to a
complementary study by the groups of D. N. Basov (Columbia University, New York) and colleagues as well as Alexey Chernikov (TU Dresden) to identify a new exciton species living exquisitely at the surfaces of the quasi-one-dimensional semiconductor: so-called surface excitons.
For further information, please visit the press department of the university (
German/
English) or the
News & Views article of Nature Materials.
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2025-02-12
© 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).
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2024-07-17
© 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.
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2024-07-12
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.
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2024-05-08
© 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.
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2024-03-14
© 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....
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2024-02-28
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....
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2024-02-09
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...
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2023-11-08
© 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....
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