@inproceedings{37329, author = {{Trautmann, Alexander and Zuo, Ruixin and Wang, Guifang and Hannes, Wolf-Rüdiger and Yang, Shidong and Thong, Le Huu and Ngo, Cong and Steiner, Johannes and Ciappina, Marcelo and Reichelt, Matthias and Duc, Huynh Thanh and Song, Xiaohong and Yang, Weifeng and Meier, Torsten}}, booktitle = {{Ultrafast Phenomena and Nanophotonics XXVI}}, editor = {{Betz, Markus and Elezzabi, Abdulhakem Y.}}, title = {{{Microscopic simulations of high harmonic generation from semiconductors}}}, doi = {{10.1117/12.2607447}}, volume = {{11999}}, year = {{2022}}, } @article{25605, abstract = {{The nonlinear process of second harmonic generation (SHG) in monolayer (1L) transition metal dichalcogenides (TMD), like WS2, strongly depends on the polarization state of the excitation light. By combination of plasmonic nanostructures with 1L-WS2 by transferring it onto a plasmonic nanoantenna array, a hybrid metasurface is realized impacting the polarization dependency of its SHG. Here, we investigate how plasmonic dipole resonances affect the process of SHG in plasmonic–TMD hybrid metasurfaces by nonlinear spectroscopy. We show that the polarization dependency is affected by the lattice structure of plasmonic nanoantenna arrays as well as by the relative orientation between the 1L-WS2 and the individual plasmonic nanoantennas. In addition, such hybrid metasurfaces show SHG in polarization states, where SHG is usually forbidden for either 1L-WS2 or plasmonic nanoantennas. By comparing the SHG in these channels with the SHG generated by the hybrid metasurface components, we detect an enhancement of the SHG signal by a factor of more than 40. Meanwhile, an attenuation of the SHG signal in usually allowed polarization states is observed. Our study provides valuable insight into hybrid systems where symmetries strongly affect the SHG and enable tailored SHG in 1L-WS2 for future applications.}}, author = {{Spreyer, Florian and Ruppert, Claudia and Georgi, Philip and Zentgraf, Thomas}}, issn = {{1936-0851}}, journal = {{ACS Nano}}, number = {{10}}, pages = {{16719--16728}}, title = {{{Influence of Plasmon Resonances and Symmetry Effects on Second Harmonic Generation in WS2–Plasmonic Hybrid Metasurfaces}}}, doi = {{10.1021/acsnano.1c06693}}, volume = {{15}}, year = {{2021}}, } @article{37331, abstract = {{High harmonic generation (HHG) from solids shows great application prospects in compact short-wavelength light sources and as a tool for imaging the dynamics in crystals with subnanometer spatial and attosecond temporal resolution. However, the underlying collision dynamics behind solid HHG is still intensively debated and no direct mapping relationship between the collision dynamics with band structure has been built. Here, we show that the electron and its associated hole can be elastically scattered by neighboring atoms when their wavelength approaches the atomic size. We reveal that the elastic scattering of electron/hole from neighboring atoms can dramatically influence the electron recombination with its left-behind hole, which turns out to be the fundamental reason for the anisotropic interband HHG observed recently in bulk crystals. Our findings link the electron/hole backward scattering with Van Hove singularities and forward scattering with critical lines in the band structure and thus build a clear mapping between the band structure and the harmonic spectrum. Our work provides a unifying picture for several seemingly unrelated experimental observations and theoretical predictions, including the anisotropic harmonic emission in MgO, the atomic-like recollision mechanism of solid HHG, and the delocalization of HHG in ZnO. This strongly improved understanding will pave the way for controlling the solid-state HHG and visualizing the structure-dependent electron dynamics in solids.}}, author = {{Zuo, Ruixin and Trautmann, Alexander and Wang, Guifang and Hannes, Wolf-Rüdiger and Yang, Shidong and Song, Xiaohong and Meier, Torsten and Ciappina, Marcelo and Duc, Huynh Thanh and Yang, Weifeng}}, issn = {{2765-8791}}, journal = {{Ultrafast Science}}, publisher = {{American Association for the Advancement of Science (AAAS)}}, title = {{{Neighboring Atom Collisions in Solid-State High Harmonic Generation}}}, doi = {{10.34133/2021/9861923}}, volume = {{2021}}, year = {{2021}}, } @article{37333, author = {{Krauss-Kodytek, L. and Hannes, W.-R. and Meier, Torsten and Ruppert, C. and Betz, M.}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, number = {{8}}, publisher = {{American Physical Society (APS)}}, title = {{{Nondegenerate two-photon absorption in ZnSe: Experiment and theory}}}, doi = {{10.1103/physrevb.104.085201}}, volume = {{104}}, year = {{2021}}, } @article{23472, author = {{Krauss-Kodytek, L. and Hannes, Wolf-Rüdiger and Meier, Torsten and Ruppert, C. and Betz, M.}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, number = {{8}}, title = {{{Nondegenerate two-photon absorption in ZnSe: Experiment and theory}}}, doi = {{10.1103/physrevb.104.085201}}, volume = {{104}}, year = {{2021}}, } @inproceedings{20770, author = {{Hannes, Wolf-Rüdiger and Meier, Torsten}}, booktitle = {{Ultrafast Phenomena and Nanophotonics XXIV}}, editor = {{Betz, Markus and Elezzabi, Abdulhakem Y.}}, isbn = {{9781510633193}}, pages = {{112780S}}, title = {{{k.p-based multiband simulations of non-degenerate two-photon absorption in bulk GaAs}}}, doi = {{10.1117/12.2545924}}, volume = {{11278}}, year = {{2020}}, } @article{20772, author = {{Song, Xiaohong and Yang, Shidong and Zuo, Ruixin and Meier, Torsten and Yang, Weifeng}}, issn = {{2469-9926}}, journal = {{Physical Review A}}, title = {{{Enhanced high-order harmonic generation in semiconductors by excitation with multicolor pulses}}}, doi = {{10.1103/physreva.101.033410}}, volume = {{101}}, year = {{2020}}, } @inproceedings{13285, author = {{Hannes, Wolf-Rüdiger and Krauß-Kodytek, Laura and Ruppert, Claudia and Betz, Markus and Meier, Torsten}}, booktitle = {{Ultrafast Phenomena and Nanophotonics XXIII}}, editor = {{Betz, Markus and Elezzabi, Abdulhakem Y.}}, isbn = {{9781510624740}}, title = {{{Intensity-dependent degenerate and non-degenerate nonlinear optical absorption of direct-gap semiconductors}}}, doi = {{10.1117/12.2503539}}, volume = {{10916}}, year = {{2019}}, } @article{13284, author = {{Hannes, Wolf-Rüdiger and Meier, Torsten}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, number = {{12}}, title = {{{Higher-order contributions and nonperturbative effects in the nondegenerate nonlinear optical absorption of semiconductors using a two-band model}}}, doi = {{10.1103/physrevb.99.125301}}, volume = {{99}}, year = {{2019}}, } @article{13900, author = {{Song, Xiaohong and Zuo, Ruixin and Yang, Shidong and Li, Pengcheng and Meier, Torsten and Yang, Weifeng}}, issn = {{1094-4087}}, journal = {{Optics Express}}, number = {{3}}, pages = {{2225--2234}}, title = {{{Attosecond temporal confinement of interband excitation by intraband motion}}}, doi = {{10.1364/oe.27.002225}}, volume = {{27}}, year = {{2019}}, } @article{13920, abstract = {{We investigate the transient optical response in high-quality Cd0.88Zn0.12Te crystals in the regime of slow light propagation on the lower exciton-polariton branch. Femtosecond photoexcitation leads to very substantial transmission changes in a ∼10-meV broad spectral range within the transparency window of the unexcited semiconductor. These nonlinear optical signatures decay on picosecond time scales governed by carrier thermalization and recombination. The temporal and spectral dependence indicate the dynamical optical response as arising from excitation-induced dephasing and perturbed free induction decay. Model simulations for the optical response taking into account the actual exciton-polariton dispersion and excitation-induced dephasing of a nonlinearly driven two-level system support this interpretation.}}, author = {{Lohrenz, J. and Melzer, S. and Ruppert, C. and Akimov, I. A. and Mariette, H. and Reichelt, Matthias and Trautmann, Alexander and Meier, Torsten and Betz, M.}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, number = {{7}}, title = {{{Ultrafast dynamical response of the lower exciton-polariton branch in CdZnTe}}}, doi = {{10.1103/physrevb.93.075201}}, volume = {{93}}, year = {{2016}}, } @article{13910, author = {{Ma, Xuekai and Driben, Rodislav and Malomed, Boris A. and Meier, Torsten and Schumacher, Stefan}}, issn = {{2045-2322}}, journal = {{Scientific Reports}}, title = {{{Two-dimensional symbiotic solitons and vortices in binary condensates with attractive cross-species interaction}}}, doi = {{10.1038/srep34847}}, volume = {{6}}, year = {{2016}}, } @article{13919, author = {{Sternemann, E. and Jostmeier, T. and Ruppert, C. and Thunich, S. and Duc, H. T. and Podzimski, R. and Meier, Torsten and Betz, M.}}, issn = {{0946-2171}}, journal = {{Applied Physics B}}, title = {{{Quantum interference control of electrical currents in GaAs microstructures: physics and spectroscopic applications}}}, doi = {{10.1007/s00340-015-6310-y}}, volume = {{122}}, year = {{2016}}, }