@article{37280, author = {{Rose, Hendrik and Vasil'ev, A. N. and Tikhonova, O. V. and Meier, Torsten and Sharapova, Polina}}, issn = {{2469-9926}}, journal = {{Physical Review A}}, number = {{1}}, publisher = {{American Physical Society (APS)}}, title = {{{Quantum-optical excitations of semiconductor nanostructures in a microcavity using a two-band model and a single-mode quantum field}}}, doi = {{10.1103/physreva.107.013703}}, volume = {{107}}, year = {{2023}}, } @inproceedings{43189, abstract = {{The nonlinear optical response of quantum well excitons is investigated experimentally using polarization resolved four wave mixing, optical-pump optical-probe, and optical-pump Terahertz-probe spectroscopy. The four-wave mixing data reveal clear signatures of coherent biexcitons which concur with straight-forward polarization selection rules at the Γ point. The type-I samples show the well-established time-domain beating signatures in the transients as well as the corresponding spectral signatures clearly. The latter are also present in type-II samples; however, the smaller exciton and biexciton binding energies in these structures infer longer beating times which, in turn, are accompanied by faster dephasing of the type-II exciton coherences. Furthermore, the THz absorption following spectrally narrow, picosecond excitation at energies in the vicinity of the 1s exciton resonance are discussed. Here, the optical signatures yield the well-established redshifts and blueshifts for the appropriate polarization geometries in type-I quantum well samples also termed “AC Stark Effect”. The THz probe reveals intriguing spectral features which can be ascribed to coherent negative absorption following an excitation into a virtual state for an excitation below the 1s exciton resonance. Furthermore, the scattering and ionization of excitons is discussed for several excitation geometries yielding control rules for elastic and inelastic quasiparticle collisions.}}, author = {{Meier, Torsten and Stein, M. and Schäfer, F. and Anders, D. and Littmann, J. H. and Fey, M. and Trautmann, Alexander and Ngo, C. and Steiner, J. T. and Reichelt, Matthias and Fuchs, C. and Volz, K. and Chatterjee, S.}}, booktitle = {{Ultrafast Phenomena and Nanophotonics XXVII}}, publisher = {{SPIE }}, title = {{{Experimental studies of the excitonic nonlinear response of GaAs-based type-I and type-II quantum well structures interacting with optical and terahertz fields}}}, doi = {{10.1117/12.2650291}}, volume = {{12419}}, year = {{2023}}, } @inproceedings{43191, abstract = {{Anomalous currents refer to electronic currents that flow perpendicularly to the direction of the accelerating electric field. Such anomalous currents can be generated when Terahertz fields are applied after an optical interband excitation of GaAs quantum wells. The underlying processes are investigated by numerical solutions of the semiconductor Bloch equations in the length gauge. Excitonic effects are included by treating the manybody Coulomb interaction in time-dependent Hartree-Fock approximation and additionally also carrier-phonon scattering processes are considered. The band structure and matrix elements are obtained from a 14-band k · p model within the envelope function approximation. The random phase factors of the matrix elements that appear due to the separate numerical diagonalization at each k-point are treated by applying a smooth gauge transformation. We present the macroscopic Berry curvature and anomalous current transients with and without excitonic effects. It is demonstrated that the resonant optical excitation of excitonic resonances can significantly enhance the Berry curvature and the anomalous currents.}}, author = {{Meier, Torsten and Ngo, C. and Priyadarshi, S. and Duc, H. T. and Bieler, M.}}, booktitle = {{Ultrafast Phenomena and Nanophotonics XXVII}}, publisher = {{SPIE}}, title = {{{Terahertz-induced anomalous currents following the optical excitation of excitons in semiconductor quantum wells}}}, doi = {{10.1117/12.2646022}}, volume = {{12419}}, year = {{2023}}, } @inproceedings{43190, abstract = {{The nonlinear optical response of quantum well excitons excited by optical fields is analyzed by numerical solutions of the semiconductor Bloch equations. Differential absorption spectra are computed for resonant pumping at the exciton resonance and the dependence of the absorption changes on the polarization directions of the pump and probe pulses is investigated. Coherent biexcitonic many-body correlations are included in our approach up to third-order in the optical fields. Results are presented for spatially-direct type-I and spatiallyindirect type-II quantum well systems. Due to the spatial inhomogeneity, in type-II structures a finite coupling between excitons of opposite spins exists already on the Hartree-Fock level and contributes to the absorption changes for the case of opposite circularly polarized pump and probe pulses.}}, author = {{Meier, Torsten and Trautmann, Alexander and Stein, M. and Schäfer, F. and Anders, D. and Ngo, C. and Steiner, J. T. and Reichelt, Matthias and Chatterjee, S.}}, booktitle = {{Ultrafast Phenomena and Nanophotonics XXVII}}, publisher = {{SPIE}}, title = {{{Analysis of the nonlinear optical response of excitons in type-I and type-II quantum wells including many-body correlations}}}, doi = {{10.1117/12.2650169}}, volume = {{12419}}, year = {{2023}}, } @article{43139, author = {{Meier, Torsten and Schäfer, F. and Stein, M. and Lorenz, J. and Dobener, F. and Ngo, C. and Steiner, J. T. and Fuchs, C. and Stolz, W. and Volz, K. and Hader, J. and Moloney, J.V. and Koch, S.W. and Chatterjee, S.}}, journal = {{Applied Physics Letters}}, number = {{8}}, title = {{{Gain recovery dynamics in active type-II semiconductor heterostructures}}}, doi = {{10.1063/5.0128777}}, volume = {{122}}, year = {{2023}}, } @unpublished{43132, author = {{Meier, Torsten and Grisard, S. and Trifonov, A.V. and Rose, Hendrik and Reichhardt, R. and Reichelt, Matthias and Schneider, C. and Kamp, M. and Höfling, S. and Bayer, M. and Akimov, I.A}}, booktitle = {{arxiv:2302.02480}}, title = {{{Temporal sorting of optical multi-wave-mixing processes in semiconductor quantum dots}}}, year = {{2023}}, } @inproceedings{43192, abstract = {{The nonlinear optical response of an ensemble of semiconductor quantum dots is analyzed by wave-mixing processes, where we focus on four-wave mixing with two incident pulses. Wave-mixing experiments are often described with semiclassical models, where the light is modeled classically and the material quantum mechanically. Here, however, we use a fully quantized model, where the light is given by a quantum state of light. Quantum light involves more degrees of freedom than classical light as e.g., its photon statistics and quantum correlations, which is a promising resource for quantum devices, such as quantum memories. The light-matter interaction is treated with a Jaynes-Cummings type model and the quantum field is given by a single mode since the quantum dots are embedded in a microcavity. We present numerical simulations of the four-wave-mixing response of a homogeneous system for pulse sequences and find a significant dependence of the result on the photon statistics of the incident pulses. The model constitutes a problem with a large state space which arises from the frequency distribution of the transition energies of the inhomogeneously broadened quantum dot ensemble that is coupled with a quantum light mode. Here we approximate the dynamics by summing over individual quantum dot-microcavity systems. Photon echoes arising from the excitation with different quantum states of light are simulated and compared.}}, author = {{Rose, Hendrik and Grisard, S. and Trifonov, A. V. and Reichhardt, R. and Reichelt, Matthias and Bayer, M. and Akimov, I. A. and Meier, Torsten}}, booktitle = {{Ultrafast Phenomena and Nanophotonics XXVII}}, publisher = {{SPIE}}, title = {{{Theoretical analysis of four-wave mixing on semiconductor quantum dot ensembles with quantum light}}}, doi = {{10.1117/12.2647700}}, volume = {{12419}}, year = {{2023}}, } @article{45704, abstract = {{Since high-order harmonic generation (HHG) from atoms depends sensitively on the polarization of the driving laser field, the polarization gating (PG) technique was developed and applied successfully to generate isolated attosecond pulses from atomic gases. The situation is, however, different in solid-state systems as it has been demonstrated that due to collisions with neighboring atomic cores of the crystal lattice strong HHG can be generated even by elliptically- and circularly-polarized laser fields. Here we apply PG to solid-state systems and find that the conventional PG technique is inefficient for the generation of isolated ultrashort harmonic pulse bursts. In contrast, we demonstrate that a polarization-skewed laser pulse is able to confine the harmonic emission to a time window of less than one-tenth of the laser cycle. This method provides a novel way to control HHG and to generate isolated attosecond pulses in solids.}}, author = {{Song, Xiaohong and Yang, Shidong and Wang, Guifang and Lin, Jianpeng and Wang, Liang and Meier, Torsten and Yang, Weifeng}}, issn = {{1094-4087}}, journal = {{Optics Express}}, keywords = {{Atomic and Molecular Physics, and Optics}}, number = {{12}}, publisher = {{Optica Publishing Group}}, title = {{{Control of the electron dynamics in solid-state high harmonic generation on ultrafast time scales by a polarization-skewed laser pulse}}}, doi = {{10.1364/oe.491418}}, volume = {{31}}, year = {{2023}}, } @article{45703, author = {{Zuo, Ruixin and Song, Xiaohong and Ben, Shuai and Meier, Torsten and Yang, Weifeng}}, issn = {{2643-1564}}, journal = {{Physical Review Research}}, keywords = {{General Physics and Astronomy}}, number = {{2}}, publisher = {{American Physical Society (APS)}}, title = {{{Revealing the nonadiabatic tunneling dynamics in solid-state high harmonic generation}}}, doi = {{10.1103/physrevresearch.5.l022040}}, volume = {{5}}, year = {{2023}}, } @article{45709, author = {{Belobo, D. Belobo and Meier, Torsten}}, issn = {{2211-3797}}, journal = {{Results in Physics}}, keywords = {{General Physics and Astronomy}}, publisher = {{Elsevier BV}}, title = {{{Manipulation of nonautonomous nonlinear wave solutions of the generalized coupled Gross–Pitaevskii equations with spin–orbit interaction and weak Raman couplings}}}, doi = {{10.1016/j.rinp.2023.106655}}, year = {{2023}}, }