Ultrafast solid-state quantum optics and nanophotonics

Prof. Dr. Rudolf Bratschitsch

Dr. Rudolf Bratschitsch

 

   


"Controlling light and matter on ultrafast and ultrasmall scales"


News

Anna Blob has received the Best Poster Award at the "8th NRW Nano Conference" in Dortmund.

The next "International Conference on Nonlinear Optics and Excitation Kinetics in Semiconductors" (NOEKS 15) will be held in Münster in 2020.

© Daniel Wigger

Rudolf Bratschitsch gives a public lecture on the Nobel Prize in Physics 2010 (Graphene).

© AG Bratschitsch

Together with the  group of Manfred Albrecht (University of Augsburg) we present ultrafast spintronic THz emitters based on TbFe/Pt. In particular, we show how the THz generation is governed by the composition of the ferrimagnet and the external magnetic field.

Magnetic-field-dependent THz emission of spintronic TbFe/Pt layers, R. Schneider, M. Fix, R. Heming, S. Michaelis de Vasconcellos, M. Albrecht, and R. Bratschitsch, ACS Photonics 5 (10), 3936-3942   (2018)

Ashish Arora has received the Best Poster Award at the "Flatlands Beyond Graphene 2018" conference in Leipzig.

© AG Bratschitsch

Together with the theory group of Michael Rohlfing (University of Münster) and the group of Marek Potemski (High magnetic field lab in Grenoble, France) we report on interlayer excitons in Se-based bulk transition metal dichalcogenides.

Valley-contrasting optics of interlayer excitons in Mo- and W-based bulk transition metal dichalcogenides, A. Arora, T. Deilmann, P. Marauhn, M. Drüppel, R. Schneider, M. R. Molas, D. Vaclavkova, S. Michaelis de Vasconcellos, M. Rohlfing, M. Potemski, and R. Bratschitsch, Nanoscale 10, 15571-15577 (2018)

Ashish Arora has received the Best Poster Award at the "3rd International Conference on 2D Crystals" in Malta.

© www.girls-day.de

We will show high school students how the thinnest material on earth (graphene) can be made by simple means at the Girl's day (26.04.2018).


2D Materials article published

© AG Bratschitsch

Together with the group of Marko Kralj (Institute of Physics, Croatia) we demonstrate that MoS2 monolayers grown by chemical vapor deposition (CVD) have the same mechanical properties as monolayers, which are exfoliated from natural molybdenite crystals. In CVD-grown monolayers, the applied tensile strain is fully transferred across grain boundaries between differently oriented monolayer crystal domains. Our work demonstrates that large-area CVD-grown MoS2 monolayers are promising for mass-produced nanomechanical devices. 

Strain transfer across grain boundaries in MoS2 monolayers grown by chemical vapor deposition, I. Niehues, A. Blob, T. Stiehm, R. Schmidt, ,

© DPG

Together with Andres Castellanos-Gomez (Madrid), Thomas Heine (Leipzig), and Ulf Wiedwald (Duisburg-Essen) we organize the symposium “2D Materials” at the spring meeting of the German Physical Society (DPG) in Berlin, March 11-16, 2018.

Nature Communications and 2D Materials article published

Together with the theory groups of Ermin Malic (Chalmers University of Technology, Sweden) and Andreas Knorr (TU Berlin) we reveal a new type of coupling (Dexter-like) between states of equal spin in the K and K' valleys in a 2D semiconductor. It results in an inverted valley polarization and broadening of excitonic resonances.

Inverted valley polarization in optically excited transition metal dichalcogenides, G. Berghäuser, I. Bernal-Villamil, R. Schmidt, R. Schneider, I. Niehues, P. Erhart, S. Michaelis de Vasconcellos, R. Bratschitsch, A. Knorr, and E. Malic, Nature Communications 9, 971 (2018)

Exciton broadening and band renormalization due to Dexter-like intervalley coupling, I. Bernal-Villamil, G. Berghäuser, M. Selig, I. Niehues, R. Schmidt, R. Schneider, P. Tonndorf, P. Erhart, S. Michaelis de Vasconcellos, R. Bratschitsch, A. Knorr, and E. Malic,  2D Materials 5, 025011 (2018)

Nano Letter published

© AG Bratschitsch

Together with the groups of Michael Rohlfing (Münster), Ermin Malic (Chalmers University of Technology, Sweden), Andreas Knorr (TU Berlin), Tilmann Kuhn (Münster), and Andres Castellanos-Gomez (Madrid) we show that the excitonic line width in atomically thin semiconductors can be controlled by mechanical strain.

Strain control of exciton-phonon coupling in atomically thin semiconductors, I. Niehues, R. Schmidt, M. Drüppel, P. Marauhn, D. Christiansen, M. Selig, G. Berghäuser, D. Wigger, R. Schneider, L. Braasch, R. Koch, A. Castellanos-Gomez, T. Kuhn, A. Knorr, E. Malic, M. Rohlfing, S. Michaelis de Vasconcellos, and R. Bratschitsch, Nano Letters, DOI: 10.1021/acs.nanolett.7b04868 (2018)

© privat

Our PhD students Robert Schneider, Johann Preuß, and Iris Niehues (from left to right on photo) have attended the Alfried Krupp prize ceremony at the Villa Hügel in Essen. They met with previous awardees to discuss career paths in science and listened to the presentations of Immanuel Bloch (MPQ Munich) and this year's winner Alexander Szameit (University of Rostock).

OPON 2018

© D. Wigger

We are co-organizing the 5th International Workshop on the Optical Properties of Nanostructures (OPON 2018) in Münster, 14-16 February 2018. The abstract submission deadline is 15 December 2017.

Physical Review Letter published

© AG Bratschitsch

Together with the theory groups of Andreas Knorr (TU Berlin) and Ermin Malic (Chalmers University of Technology, Sweden) we explain how exciton-phonon scattering governs the excitonic line shape of atomically thin semiconductors.

Phonon sidebands in monolayer transition metal dichalcogenides, D. Christiansen, M. Selig, G. Berghäuser, R. Schmidt, I. Niehues, R. Schneider, A. Arora, S. Michaelis de Vasconcellos, R. Bratschitsch, E. Malic, and A. Knorr Phys. Rev. Lett. 119, 187402 (2017)

Highlights der Physik

© AG Bratschitsch
© AG Bratschitsch

We participated in the "Highlights der Physik" science fair (18-23 September 2017) in Münster with our booth about carbon structures (diamond, graphite, carbon nanotubes, fullerenes, and graphene).

Nature Communications published

© AG Bratschitsch

Together with the theory group of Michael Rohlfing (University of Münster) and Marek Potemski (High magnetic field lab in Grenoble, France) we report on interlayer excitons in a layered bulk semiconductor (MoTe2).

Interlayer excitons in a bulk van der Waals semiconductor, A. Arora, M. Drüppel, R. Schmidt, T. Deilmann, R. Schneider, M. R. Molas, P. Marauhn, S. Michaelis de Vasconcellos, M. Potemski, M. Rohlfing, and R. Bratschitsch Nature Communications 8, 639 (2017)

Nano Letters published

© AG Bratschitsch

Together with the groups of Wolfram Pernice (University of Münster) and Alexander Tartakovskii (University of Sheffield, UK) we have coupled a single-photon emitter in the layered semiconductor GaSe into a dielectric waveguide on a photonic chip.

On-chip waveguide coupling of a layered semiconductor single-photon source, P. Tonndorf, O. Del Pozo Zamudio, N. Gruhler, J. Kern, R. Schmidt, A. I. Dmitriev, A. P. Bakhtinov, A. I. Tartakovskii, W. HP Pernice, S. Michaelis de Vasconcellos, and R. Bratschitsch Nano Lett. 17, 5446 (2017)