@article{23816, abstract = {{Employing the ultrafast control of electronic states of a semiconductor quantum dot in a cavity, we introduce an approach to achieve on-demand emission of single photons with almost perfect indistinguishability and photon pairs with near ideal entanglement. Our scheme is based on optical excitation off resonant to a cavity mode followed by ultrafast control of the electronic states using the time-dependent quantum-confined Stark effect, which then allows for cavity-resonant emission. Our theoretical analysis considers cavity-loss mechanisms, the Stark effect, and phonon-induced dephasing, allowing realistic predictions for finite temperatures.}}, author = {{Bauch, David and Heinze, Dirk Florian and Förstner, Jens and Jöns, Klaus and Schumacher, Stefan}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, keywords = {{tet_topic_qd}}, pages = {{085308}}, title = {{{Ultrafast electric control of cavity mediated single-photon and photon-pair generation with semiconductor quantum dots}}}, doi = {{10.1103/physrevb.104.085308}}, volume = {{104}}, year = {{2021}}, } @article{39653, abstract = {{AbstractA detailed investigation of the energy levels of perylene-3,4,9,10-tetracarboxylic tetraethylester as a representative compound for the whole family of perylene esters was performed. It was revealed via electrochemical measurements that one oxidation and two reductions take place. The bandgaps determined via the electrochemical approach are in good agreement with the optical bandgap obtained from the absorption spectra via a Tauc plot. In addition, absorption spectra in dependence of the electrochemical potential were the basis for extensive quantum-chemical calculations of the neutral, monoanionic, and dianionic molecules. For this purpose, calculations based on density functional theory were compared with post-Hartree–Fock methods and the CAM-B3LYP functional proved to be the most reliable choice for the calculation of absorption spectra. Furthermore, spectral features found experimentally could be reproduced with vibronic calculations and allowed to understand their origins. In particular, the two lowest energy absorption bands of the anion are not caused by absorption of two distinct electronic states, which might have been expected from vertical excitation calculations, but both states exhibit a strong vibronic progression resulting in contributions to both bands.}}, author = {{Wiebeler, Christian and Vollbrecht, Joachim and Neuba, Adam and Kitzerow, Heinz-Siegfried and Schumacher, Stefan}}, issn = {{2045-2322}}, journal = {{Scientific Reports}}, keywords = {{Multidisciplinary}}, number = {{1}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Unraveling the electrochemical and spectroscopic properties of neutral and negatively charged perylene tetraethylesters}}}, doi = {{10.1038/s41598-021-95551-0}}, volume = {{11}}, year = {{2021}}, } @article{40434, author = {{Klement, Philip and Dehnhardt, Natalie and Dong, Chuan-Ding and Dobener, Florian and Bayliff, Samuel and Winkler, Julius and Hofmann, Detlev M. and Klar, Peter J. and Schumacher, Stefan and Chatterjee, Sangam and Heine, Johanna}}, issn = {{0935-9648}}, journal = {{Advanced Materials}}, keywords = {{Mechanical Engineering, Mechanics of Materials, General Materials Science}}, number = {{23}}, publisher = {{Wiley}}, title = {{{Atomically Thin Sheets of Lead‐Free 1D Hybrid Perovskites Feature Tunable White‐Light Emission from Self‐Trapped Excitons}}}, doi = {{10.1002/adma.202100518}}, volume = {{33}}, year = {{2021}}, } @article{21359, author = {{Barkhausen, Franziska and Pukrop, Matthias and Schumacher, Stefan and Ma, Xuekai}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, number = {{7}}, title = {{{Structuring coflowing and counterflowing currents of polariton condensates in concentric ring-shaped and elliptical potentials}}}, doi = {{10.1103/physrevb.103.075305}}, volume = {{103}}, year = {{2021}}, } @article{24975, author = {{Franz, Martin and Chandola, Sandhya and Koy, Maximilian and Zielinski, Robert and Aldahhak, Hazem and Das, Mowpriya and Freitag, Matthias and Gerstmann, Uwe and Liebig, Denise and Hoffmann, Adrian Karl and Rosin, Maximilian and Schmidt, Wolf Gero and Hogan, Conor and Glorius, Frank and Esser, Norbert and Dähne, Mario}}, issn = {{1755-4330}}, journal = {{Nature Chemistry}}, pages = {{828--835}}, title = {{{Controlled growth of ordered monolayers of N-heterocyclic carbenes on silicon}}}, doi = {{10.1038/s41557-021-00721-2}}, year = {{2021}}, } @article{23418, abstract = {{Density-functional theory within a Berry-phase formulation of the dynamical polarization is used to determine the second-order susceptibility χ(2) of lithium niobate (LiNbO3). Defect trapped polarons and bipolarons are found to strongly enhance the nonlinear susceptibility of the material, in particular if localized at NbV–VLi defect pairs. This is essentially a consequence of the polaronic excitation resulting in relaxation-induced gap states. The occupation of these levels leads to strongly enhanced χ(2) coefficients and allows for the spatial and transient modification of the second-harmonic generation of macroscopic samples.}}, author = {{Kozub, Agnieszka L. and Schindlmayr, Arno and Gerstmann, Uwe and Schmidt, Wolf Gero}}, issn = {{2469-9969}}, journal = {{Physical Review B}}, pages = {{174110}}, publisher = {{American Physical Society}}, title = {{{Polaronic enhancement of second-harmonic generation in lithium niobate}}}, doi = {{10.1103/PhysRevB.104.174110}}, volume = {{104}}, year = {{2021}}, } @inproceedings{23475, author = {{Rose, Hendrik and Paul, Jagannath and Wahlstrand, Jared K. and Bristow, Alan D. and Meier, Torsten}}, booktitle = {{Ultrafast Phenomena and Nanophotonics XXV}}, editor = {{Betz, Markus and Elezzabi, Abdulhakem Y.}}, title = {{{Theoretical analysis and simulations of two-dimensional Fourier transform spectroscopy performed on exciton-polaritons of a quantum-well microcavity system}}}, doi = {{10.1117/12.2576696}}, volume = {{11684}}, 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{21547, author = {{Riabinin, Matvei and Sharapova, Polina and Bartley, Tim and Meier, Torsten}}, issn = {{2399-6528}}, journal = {{Journal of Physics Communications}}, number = {{4}}, title = {{{Generating two-mode squeezing with multimode measurement-induced nonlinearity}}}, doi = {{10.1088/2399-6528/abeec2}}, volume = {{5}}, 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}}, }