@article{20372,
abstract = {{A stepwise angular spectrum method (SASM) for curved interfaces is presented to calculate the wave propagation in planar lens-like integrated optical structures based on photonic slab waveguides. The method is derived and illustrated for an effective 2D setup first and then for 3D slab waveguide lenses. We employ slab waveguides of different thicknesses connected by curved surfaces to realize a lens-like structure. To simulate the wave propagation in 3D including reflection and scattering losses, the stepwise angular spectrum method is combined with full vectorial finite element computations for subproblems with lower complexity. Our SASM results show excellent agreement with rigorous numerical simulations of the full structures with a substantially lower computational effort and can be utilized for the simulation-based design and optimization of complex and large scale setups.}},
author = {{Ebers, Lena and Hammer, Manfred and Förstner, Jens}},
issn = {{1094-4087}},
journal = {{Optics Express}},
keywords = {{tet_topic_waveguides}},
number = {{24}},
pages = {{36361}},
title = {{{Light diffraction in slab waveguide lenses simulated with the stepwise angular spectrum method}}},
doi = {{10.1364/oe.409612}},
volume = {{28}},
year = {{2020}},
}
@article{20644,
abstract = {{Plasmonic nanoantennas for visible and infrared radiation strongly improve the interaction of light with the matter on the nanoscale due to their strong near-field enhancement. In this study, we investigate a double-resonant plasmonic nanoantenna, which makes use of plasmonic field enhancement, enhanced outcoupling of second harmonic light, and resonant lattice effects. Using this design, we demonstrate how the efficiency of second harmonic generation can be increased significantly by fully embedding the nanoantennas into nonlinear dielectric material ZnO, instead of placing them on the surface. Investigating two different processes, we found that the best fabrication route is embedding the gold nanoantennas in ZnO using an MBE overgrowth process where a thin ZnO layer was deposited on nanoantennas fabricated on a ZnO substrate. In addition, second harmonic generation measurements show that the embedding leads to an enhancement compared to the emission of nanoantennas placed on the ZnO substrate surface. These promising results facilitate further research to determine the influence of the periodicity of the nanoantenna arrangement of the resulting SHG signal.}},
author = {{Volmert, Ruth and Weber, Nils and Meier, Cedrik}},
issn = {{1089-7550}},
journal = {{Journal of Applied Physics}},
number = {{4}},
title = {{{Nanoantennas embedded in zinc oxide for second harmonic generation enhancement}}},
doi = {{10.1063/5.0012813}},
volume = {{128}},
year = {{2020}},
}
@inproceedings{21719,
abstract = {{We fabricate silicon tapers to increase the mode overlap of superconducting detectors on Ti:LiNbO3 waveguides. Mode images show a reduction in mode size from 6 µm to 2 µm FWHM, agreeing with beam propagation simulations.}},
author = {{Protte, Maximilian and Ebers, Lena and Hammer, Manfred and Höpker, Jan Philipp and Albert, Maximilian and Quiring, Viktor and Meier, Cedrik and Förstner, Jens and Silberhorn, Christine and Bartley, Tim}},
booktitle = {{OSA Quantum 2.0 Conference}},
isbn = {{9781943580811}},
keywords = {{tet_topic_waveguide}},
title = {{{Towards Semiconductor-Superconductor-Crystal Hybrid Integration for Quantum Photonics}}},
doi = {{10.1364/quantum.2020.qth7a.8}},
year = {{2020}},
}
@article{17322,
author = {{Mukherjee, Amlan and Widhalm, Alex and Siebert, Dustin and Krehs, Sebastian and Sharma, Nandlal and Thiede, Andreas and Reuter, Dirk and Förstner, Jens and Zrenner, Artur}},
issn = {{0003-6951}},
journal = {{Applied Physics Letters}},
keywords = {{tet_topic_qd}},
pages = {{251103}},
title = {{{Electrically controlled rapid adiabatic passage in a single quantum dot}}},
doi = {{10.1063/5.0012257}},
volume = {{116}},
year = {{2020}},
}
@article{21025,
author = {{Eigner, Christof and Padberg, Laura and Santandrea, Matteo and Herrmann, Harald and Brecht, Benjamin and Silberhorn, Christine}},
issn = {{1094-4087}},
journal = {{Optics Express}},
number = {{22}},
title = {{{Spatially single mode photon pair source at 800 nm in periodically poled Rubidium exchanged KTP waveguides}}},
doi = {{10.1364/oe.399483}},
volume = {{28}},
year = {{2020}},
}
@article{17067,
author = {{Speiser, Eugen and Esser, Norbert and Halbig, Benedikt and Geurts, Jean and Schmidt, Wolf Gero and Sanna, Simone}},
issn = {{0167-5729}},
journal = {{Surface Science Reports}},
number = {{1}},
title = {{{Vibrational Raman spectroscopy on adsorbate-induced low-dimensional surface structures}}},
doi = {{10.1016/j.surfrep.2020.100480}},
volume = {{75}},
year = {{2020}},
}
@article{20582,
author = {{Berger, Bernd and Schmidt, Daniel and Ma, Xuekai and Schumacher, Stefan and Schneider, Christian and Höfling, Sven and Assmann, Marc}},
journal = {{Physical Review B}},
number = {{24}},
pages = {{245309}},
publisher = {{American Physical Society}},
title = {{{Formation dynamics of exciton-polariton vortices created by nonresonant annular pumping}}},
doi = {{10.1103/PhysRevB.101.245309}},
volume = {{101}},
year = {{2020}},
}
@article{19190,
abstract = {{Polarons in dielectric crystals play a crucial role for applications in integrated electronics and optoelectronics. In this work, we use density-functional theory and Green's function methods to explore the microscopic structure and spectroscopic signatures of electron polarons in lithium niobate (LiNbO3). Total-energy calculations and the comparison of calculated electron paramagnetic resonance data with available measurements reveal the formation of bound
polarons at Nb_Li antisite defects with a quasi-Jahn-Teller distorted, tilted configuration. The defect-formation energies further indicate that (bi)polarons may form not only at
Nb_Li antisites but also at structures where the antisite Nb atom moves into a neighboring empty oxygen octahedron. Based on these structure models, and on the calculated charge-transition levels and potential-energy barriers, we propose two mechanisms for the optical and thermal splitting of bipolarons, which provide a natural explanation for the reported two-path recombination of bipolarons. Optical-response calculations based on the Bethe-Salpeter equation, in combination with available experimental data and new measurements of the optical absorption spectrum, further corroborate the geometries proposed here for free and defect-bound (bi)polarons.}},
author = {{Schmidt, Falko and Kozub, Agnieszka L. and Biktagirov, Timur and Eigner, Christof and Silberhorn, Christine and Schindlmayr, Arno and Schmidt, Wolf Gero and Gerstmann, Uwe}},
issn = {{2643-1564}},
journal = {{Physical Review Research}},
number = {{4}},
publisher = {{American Physical Society}},
title = {{{Free and defect-bound (bi)polarons in LiNbO3: Atomic structure and spectroscopic signatures from ab initio calculations}}},
doi = {{10.1103/PhysRevResearch.2.043002}},
volume = {{2}},
year = {{2020}},
}
@article{40444,
author = {{von Bardeleben, H. J. and Rauls, E. and Gerstmann, Uwe}},
issn = {{2469-9950}},
journal = {{Physical Review B}},
number = {{18}},
publisher = {{American Physical Society (APS)}},
title = {{{Carbon vacancy-related centers in 3C-silicon carbide: Negative-U properties and structural transformation}}},
doi = {{10.1103/physrevb.101.184108}},
volume = {{101}},
year = {{2020}},
}
@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{20563,
author = {{Hannes, W.-R. and Trautmann, Alexander and Stein, M. and Schäfer, F. and Koch, M. and Meier, Torsten}},
journal = {{Physical Review B}},
number = {{7}},
pages = {{075203}},
publisher = {{American Physical Society}},
title = {{{Strongly nonresonant four-wave mixing in semiconductors}}},
doi = {{10.1103/PhysRevB.101.075203}},
volume = {{101}},
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}},
}
@article{20682,
author = {{Bocchini, Adriana and Eigner, Christof and Silberhorn, Christine and Schmidt, Wolf Gero and Gerstmann, Uwe}},
journal = {{Phys. Rev. Materials}},
pages = {{124402}},
publisher = {{American Physical Society}},
title = {{{Understanding gray track formation in KTP: Ti^3+ centers studied from first principles}}},
doi = {{10.1103/PhysRevMaterials.4.124402}},
volume = {{4}},
year = {{2020}},
}
@article{58080,
author = {{Demenev, A.A. and Gavrilov, S.S. and Sherbakov, A. V. and Yaremkevich, D. D. and Kukhtaruk, S. M. and Yakovlev, D. R. and Kulakovskii, V. D. and Bayer, M. }},
journal = {{ Journal of Physics: Conference Series}},
title = {{{Ultrafast acoustic switching of an optically pumped cavity polariton system in the bistable regime}}},
doi = {{10.1088/1742-6596/1461/1/012077}},
volume = {{1461}},
year = {{2020}},
}
@article{58081,
author = {{Kobecki, Michal and Tandoi, Giuseppe and Di Gaetano, Eugenio and Sorel, Marc and Scherbakov, Alexey V. and Czerniuk, Thomas and Schneider, Christian and Kamp, Martin and Höfling, Sven and Akimov, Andrey V. and Bayer, Manfred }},
journal = {{Ultrasonics}},
publisher = {{Elsevier}},
title = {{{Picosecond ultrasonics with miniaturized semiconductor lasers}}},
doi = {{10.1016/j.ultras.2020.106150}},
volume = {{106}},
year = {{2020}},
}
@inproceedings{39966,
author = {{Förstner, Jens and Widhalm, A. and Mukherjee, A. and Krehs, S. and Jonas, B. and Spychala, K. and Förstner, Jens and Thiede, Andreas and Reuter, Dirk and Zrenner, Artur}},
booktitle = {{11th International Conference on Quantum Dots}},
title = {{{Ultrafast electric control of a single QD exciton}}},
year = {{2020}},
}
@article{20580,
author = {{Ma, Xuekai and Berger, B and Aßmann, M and Driben, R and Meier, Torsten and Schneider, C and Höfling, S and Schumacher, Stefan}},
issn = {{2041-1723}},
journal = {{Nature Communications}},
number = {{1}},
pages = {{897}},
title = {{{Realization of all-optical vortex switching in exciton-polariton condensates}}},
doi = {{10.1038/s41467-020-14702-5}},
volume = {{11}},
year = {{2020}},
}
@article{20584,
author = {{Ren, J and Liao, Q and Huang, H and Li, Y and Gao, T and Ma, Xuekai and Schumacher, Stefan and Yao, J and Bai, S and Fu, H}},
issn = {{1530-6992}},
journal = {{Nano Letters}},
number = {{10}},
pages = {{7550--7557}},
title = {{{Efficient Bosonic Condensation of Exciton Polaritons in an H-Aggregate Organic Single-Crystal Microcavity.}}},
doi = {{10.1021/acs.nanolett.0c03009}},
volume = {{20}},
year = {{2020}},
}
@article{20585,
author = {{Ma, Xuekai and Kartashov, YV and Ferrando, A and Schumacher, Stefan}},
issn = {{0146-9592}},
journal = {{Optics Letters}},
number = {{19}},
pages = {{5311--5314}},
title = {{{Topological edge states of nonequilibrium polaritons in hollow honeycomb arrays.}}},
doi = {{10.1364/ol.405844}},
volume = {{45}},
year = {{2020}},
}
@article{20587,
author = {{Barkhausen, F and Schumacher, Stefan and Ma, Xuekai}},
issn = {{0146-9592}},
journal = {{Optics Letters}},
number = {{5}},
pages = {{1192--1195}},
title = {{{Multistable circular currents of polariton condensates trapped in ring potentials.}}},
doi = {{10.1364/ol.386250}},
volume = {{45}},
year = {{2020}},
}