@article{10021, abstract = {{The optical properties of pristine and titanium-doped LiNbO3 are modeled from first principles. The dielectric functions are calculated within time-dependent density-functional theory, and a model long-range contribution is employed for the exchange-correlation kernel in order to account for the electron-hole binding. Our study focuses on the influence of substitutional titanium atoms on lithium sites. We show that an increasing titanium concentration enhances the values of the refractive indices and the reflectivity.}}, author = {{Friedrich, Michael and Schmidt, Wolf Gero and Schindlmayr, Arno and Sanna, Simone}}, issn = {{2475-9953}}, journal = {{Physical Review Materials}}, number = {{3}}, publisher = {{American Physical Society}}, title = {{{Optical properties of titanium-doped lithium niobate from time-dependent density-functional theory}}}, doi = {{10.1103/PhysRevMaterials.1.034401}}, volume = {{1}}, year = {{2017}}, } @article{13424, author = {{Aldahhak, Hazem and Paszkiewicz, M. and Allegretti, F. and Duncan, D. A. and Tebi, S. and Deimel, P. S. and Casado Aguilar, P. and Zhang, Y.-Q. and Papageorgiou, A. C. and Koch, R. and Barth, J. V. and Schmidt, Wolf Gero and Müllegger, S. and Schöfberger, W. and Klappenberger, F. and Rauls, E. and Gerstmann, Uwe}}, issn = {{1932-7447}}, journal = {{The Journal of Physical Chemistry C}}, pages = {{2192--2200}}, title = {{{X-ray Spectroscopy of Thin Film Free-Base Corroles: A Combined Theoretical and Experimental Characterization}}}, doi = {{10.1021/acs.jpcc.6b09935}}, volume = {{121}}, year = {{2017}}, } @article{13423, author = {{Tebi, Stefano and Paszkiewicz, Mateusz and Aldahhak, Hazem and Allegretti, Francesco and Gonglach, Sabrina and Haas, Michael and Waser, Mario and Deimel, Peter S. and Aguilar, Pablo Casado and Zhang, Yi-Qi and Papageorgiou, Anthoula C. and Duncan, David A. and Barth, Johannes V. and Schmidt, Wolf Gero and Koch, Reinhold and Gerstmann, Uwe and Rauls, Eva and Klappenberger, Florian and Schöfberger, Wolfgang and Müllegger, Stefan}}, issn = {{1936-0851}}, journal = {{ACS Nano}}, pages = {{3383--3391}}, title = {{{On-Surface Site-Selective Cyclization of Corrole Radicals}}}, doi = {{10.1021/acsnano.7b00766}}, year = {{2017}}, } @article{13426, author = {{Edler, F. and Miccoli, I. and Stöckmann, J. P. and Pfnür, H. and Braun, Christian and Neufeld, Sergej and Sanna, S. and Schmidt, Wolf Gero and Tegenkamp, C.}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, number = {{12}}, title = {{{Tuning the conductivity along atomic chains by selective chemisorption}}}, doi = {{10.1103/physrevb.95.125409}}, volume = {{95}}, year = {{2017}}, } @article{13427, author = {{Nozaki, Daijiro and Lücke, Andreas and Schmidt, Wolf Gero}}, issn = {{1948-7185}}, journal = {{The Journal of Physical Chemistry Letters}}, pages = {{727--732}}, title = {{{Molecular Orbital Rule for Quantum Interference in Weakly Coupled Dimers: Low-Energy Giant Conductivity Switching Induced by Orbital Level Crossing}}}, doi = {{10.1021/acs.jpclett.6b02989}}, year = {{2017}}, } @article{13425, author = {{Rohrmüller, M. and Schmidt, Wolf Gero and Gerstmann, Uwe}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, number = {{12}}, title = {{{Electron paramagnetic resonance calculations for hydrogenated Si surfaces}}}, doi = {{10.1103/physrevb.95.125310}}, volume = {{95}}, year = {{2017}}, } @article{13416, abstract = {{The optical properties of congruent lithium niobate are analyzed from first principles. The dielectric function of the material is calculated within time-dependent density-functional theory. The effects of isolated intrinsic defects and defect pairs, including the NbLi4+ antisite and the NbLi4+−NbNb4+ pair, commonly addressed as a bound polaron and bipolaron, respectively, are discussed in detail. In addition, we present further possible realizations of polaronic and bipolaronic systems. The absorption feature around 1.64 eV, ascribed to small bound polarons [O. F. Schirmer et al., J. Phys.: Condens. Matter 21, 123201 (2009)], is nicely reproduced within these models. Among the investigated defects, we find that the presence of bipolarons at bound interstitial-vacancy pairs NbV−VLi can best explain the experimentally observed broad absorption band at 2.5 eV. Our results provide a microscopic model for the observed optical spectra and suggest that, besides NbLi antisites and Nb and Li vacancies, Nb interstitials are also formed in congruent lithium-niobate samples.}}, author = {{Friedrich, Michael and Schmidt, Wolf Gero and Schindlmayr, Arno and Sanna, Simone}}, issn = {{2475-9953}}, journal = {{Physical Review Materials}}, number = {{5}}, publisher = {{American Physical Society}}, title = {{{Polaron optical absorption in congruent lithium niobate from time-dependent density-functional theory}}}, doi = {{10.1103/PhysRevMaterials.1.054406}}, volume = {{1}}, year = {{2017}}, } @article{13419, author = {{Frigge, T. and Hafke, B. and Witte, T. and Krenzer, B. and Streubühr, C. and Samad Syed, A. and Mikšić Trontl, V. and Avigo, I. and Zhou, P. and Ligges, M. and von der Linde, D. and Bovensiepen, U. and Horn-von Hoegen, M. and Wippermann, S. and Lücke, A. and Sanna, S. and Gerstmann, Uwe and Schmidt, Wolf Gero}}, issn = {{0028-0836}}, journal = {{Nature}}, pages = {{207--211}}, title = {{{Optically excited structural transition in atomic wires on surfaces at the quantum limit}}}, doi = {{10.1038/nature21432}}, volume = {{544}}, year = {{2017}}, } @article{13421, author = {{Landmann, M. and Rauls, E. and Schmidt, Wolf Gero}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, number = {{15}}, title = {{{Understanding band alignments in semiconductor heterostructures: Composition dependence and type-I–type-II transition of natural band offsets in nonpolar zinc-blendeAlxGa1−xN/AlyGa1−yNcomposites}}}, doi = {{10.1103/physrevb.95.155310}}, volume = {{95}}, year = {{2017}}, } @article{13415, author = {{Braun, Christian and Hogan, Conor and Chandola, Sandhya and Esser, Norbert and Sanna, Simone and Schmidt, Wolf Gero}}, issn = {{2475-9953}}, journal = {{Physical Review Materials}}, number = {{5}}, title = {{{Si(775)-Au atomic chains: Geometry, optical properties, and spin order}}}, doi = {{10.1103/physrevmaterials.1.055002}}, volume = {{1}}, year = {{2017}}, } @article{13422, author = {{Witte, Matthias and Rohrmüller, Martin and Gerstmann, Uwe and Henkel, Gerald and Schmidt, Wolf Gero and Herres-Pawlis, Sonja}}, issn = {{0192-8651}}, journal = {{Journal of Computational Chemistry}}, pages = {{1752--1761}}, title = {{{[Cu6(NGuaS)6]2+ and its oxidized and reduced derivatives: Confining electrons on a torus}}}, doi = {{10.1002/jcc.24798}}, year = {{2017}}, } @article{13417, author = {{Lücke, Andreas and Gerstmann, Uwe and Kühne, Thomas D. and Schmidt, Wolf Gero}}, issn = {{0192-8651}}, journal = {{Journal of Computational Chemistry}}, pages = {{2276--2282}}, title = {{{Efficient PAW-based bond strength analysis for understanding the In/Si(111)(8 × 2) - (4 × 1) phase transition}}}, doi = {{10.1002/jcc.24878}}, year = {{2017}}, } @article{13414, author = {{Riefer, A. and Schmidt, Wolf Gero}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, number = {{23}}, title = {{{Solving the Bethe-Salpeter equation for the second-harmonic generation in Zn chalcogenides}}}, doi = {{10.1103/physrevb.96.235206}}, volume = {{96}}, year = {{2017}}, } @article{13420, author = {{Nozaki, Daijiro and Schmidt, Wolf Gero}}, issn = {{0192-8651}}, journal = {{Journal of Computational Chemistry}}, pages = {{1685--1692}}, title = {{{Current density analysis of electron transport through molecular wires in open quantum systems}}}, doi = {{10.1002/jcc.24812}}, volume = {{38}}, year = {{2017}}, } @article{13418, author = {{Sanna, Simone and Schmidt, Wolf Gero}}, issn = {{0953-8984}}, journal = {{Journal of Physics: Condensed Matter}}, title = {{{LiNbO3 surfaces from a microscopic perspective}}}, doi = {{10.1088/1361-648x/aa818d}}, year = {{2017}}, } @article{13412, author = {{Konieczna, Dagny D. and Biller, Harry and Witte, Matthias and Schmidt, Wolf Gero and Neuba, Adam and Wilhelm, René}}, issn = {{0040-4020}}, journal = {{Tetrahedron}}, pages = {{142--149}}, title = {{{New pyridinium based ionic dyes for the hydrogen evolution reaction}}}, doi = {{10.1016/j.tet.2017.11.053}}, year = {{2017}}, } @article{3435, abstract = {{Semiconductor quantum dots are promising sources for polarization-entangled photons. As an alternative to the usual cascaded biexciton-exciton emission, direct two-photon emission from the biexciton can be used. With a high-quality optical resonator tuned to half the biexciton energy, a large proportion of the photons can be steered into the two-photon emission channel. In this case the degree of polarization entanglement is inherently insensitive to the exciton fine-structure splitting. In the present work we analyze the biexciton emission with particular emphasis on the influence of coupling of the quantum-dot cavity system to its environment. Especially for a high-quality cavity, the coupling to the surrounding semiconductormaterial can open up additional phonon-assisted decay channels. Our analysis demonstrates that with the cavity tuned to half the biexciton energy, the potentially detrimental influence of the phonons on the polarization entanglement is strongly suppressed—high degrees of entanglement can still be achieved. We further discuss spectral properties and statistics of the emitted twin photons.}}, author = {{Heinze, Dirk and Zrenner, Artur and Schumacher, Stefan}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{24}}, title = {{{Polarization-entangled twin photons from two-photon quantum-dot emission}}}, doi = {{10.1103/PhysRevB.95.245306}}, year = {{2017}}, } @article{13358, author = {{Vollbrecht, Joachim and Wiebeler, Christian and Schumacher, Stefan and Bock, Harald and Kitzerow, Heinz-Siegfried}}, issn = {{1542-1406}}, journal = {{Molecular Crystals and Liquid Crystals}}, pages = {{66--73}}, title = {{{Enhanced columnar mesophase range through distortions in arene cores}}}, doi = {{10.1080/15421406.2017.1284387}}, year = {{2017}}, } @article{13361, author = {{Lafont, O. and Luk, S. M. H. and Lewandowski, P. and Kwong, N. H. and Leung, P. T. and Galopin, E. and Lemaitre, A. and Tignon, J. and Schumacher, Stefan and Baudin, E. and Binder, R.}}, issn = {{0003-6951}}, journal = {{Applied Physics Letters}}, title = {{{Controlling the optical spin Hall effect with light}}}, doi = {{10.1063/1.4975681}}, year = {{2017}}, } @article{13356, author = {{Ma, Xuekai and Schumacher, Stefan}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, number = {{23}}, title = {{{Vortex-vortex control in exciton-polariton condensates}}}, doi = {{10.1103/physrevb.95.235301}}, volume = {{95}}, year = {{2017}}, }