@article{43245, abstract = {{High-contrast slab waveguide Bragg gratings with 1D periodicity are investigated. For specific oblique excitation by semi-guided waves at sufficiently high angles of incidence, the idealized structures do not exhibit any radiative losses, such that reflectance and transmittance for the single port mode add strictly up to one. We consider a series of symmetric, fully and partly etched finite gratings, for parameters found in integrated silicon photonics. These can act as spectral filters with a reasonably flattop response. Apodization can lead to more box shaped reflectance and transmittance spectra. Together with a narrowband Fabry–Perot filter, these configurations are characterized by reflection bands, or transmittance peaks, with widths that span three orders of magnitude.}}, author = {{Hammer, Manfred and Farheen, Henna and Förstner, Jens}}, issn = {{0740-3224}}, journal = {{Journal of the Optical Society of America B}}, keywords = {{tet_topic_waveguide}}, number = {{4}}, pages = {{862}}, publisher = {{Optica Publishing Group}}, title = {{{How to suppress radiative losses in high-contrast integrated Bragg gratings}}}, doi = {{10.1364/josab.485725}}, volume = {{40}}, year = {{2023}}, } @article{44081, author = {{Serino, Laura and Gil López, Jano and Stefszky, Michael and Ricken, Raimund and Eigner, Christof and Brecht, Benjamin and Silberhorn, Christine}}, issn = {{2691-3399}}, journal = {{PRX Quantum}}, keywords = {{General Physics and Astronomy, Mathematical Physics, Applied Mathematics, Electronic, Optical and Magnetic Materials, Electrical and Electronic Engineering, General Computer Science}}, number = {{2}}, publisher = {{American Physical Society (APS)}}, title = {{{Realization of a Multi-Output Quantum Pulse Gate for Decoding High-Dimensional Temporal Modes of Single-Photon States}}}, doi = {{10.1103/prxquantum.4.020306}}, volume = {{4}}, year = {{2023}}, } @book{44080, author = {{Ribbat, Christoph}}, title = {{{Breathing in Manhattan: Carola Speads - The German Jewish Gymnastics Instructor Who Brought Mindfulness to America}}}, 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}}, } @article{44050, author = {{Sperling, Jan and Agudelo, Elizabeth}}, issn = {{2469-9926}}, journal = {{Physical Review A}}, number = {{4}}, publisher = {{American Physical Society (APS)}}, title = {{{Entanglement of particles versus entanglement of fields: Independent quantum resources}}}, doi = {{10.1103/physreva.107.042420}}, volume = {{107}}, year = {{2023}}, } @article{40477, author = {{Sperling, Jan and Gianani, Ilaria and Barbieri, Marco and Agudelo, Elizabeth}}, issn = {{2469-9926}}, journal = {{Physical Review A}}, number = {{1}}, publisher = {{American Physical Society (APS)}}, title = {{{Detector entanglement: Quasidistributions for Bell-state measurements}}}, doi = {{10.1103/physreva.107.012426}}, volume = {{107}}, year = {{2023}}, }