TY - JOUR
AU - Plaickner, Julian
AU - Speiser, Eugen
AU - Braun, Christian
AU - Schmidt, Wolf Gero
AU - Esser, Norbert
AU - Sanna, Simone
ID - 22008
JF - Physical Review B
SN - 2469-9950
TI - Surface localized phonon modes at the Si(553)-Au nanowire system
ER -
TY - JOUR
AU - Meier, Lukas
AU - Schmidt, Wolf Gero
ID - 40244
IS - 1
JF - physica status solidi (b)
KW - Condensed Matter Physics
KW - Electronic
KW - Optical and Magnetic Materials
SN - 0370-1972
TI - GaInP/AlInP(001) Interfaces from Density Functional Theory
VL - 259
ER -
TY - JOUR
AU - Ruiz Alvarado, Isaac Azahel
AU - Karmo, Marsel
AU - Runge, Erich
AU - Schmidt, Wolf Gero
ID - 22009
JF - ACS Omega
SN - 2470-1343
TI - InP and AlInP(001)(2 × 4) Surface Oxidation from Density Functional Theory
ER -
TY - JOUR
AB - We perform a theoretical analysis of the structural and electronic properties of sodium potassium niobate K1-xNaxNbO3 in the orthorhombic room-temperature phase, based on density-functional theory in combination with the supercell approach. Our results for x=0 and x=0.5 are in very good agreement with experimental measurements and establish that the lattice parameters decrease linearly with increasing Na contents, disproving earlier theoretical studies based on the virtual-crystal approximation that claimed a highly nonlinear behavior with a significant structural distortion and volume reduction in K0.5Na0.5NbO3 compared to both end members of the solid solution. Furthermore, we find that the electronic band gap varies very little between x=0 and x=0.5, reflecting the small changes in the lattice parameters.
AU - Bidaraguppe Ramesh, Nithin
AU - Schmidt, Falko
AU - Schindlmayr, Arno
ID - 22960
IS - 8
JF - The European Physical Journal B
SN - 1434-6028
TI - Lattice parameters and electronic band gap of orthorhombic potassium sodium niobate K0.5Na0.5NbO3 from density-functional theory
VL - 94
ER -
TY - JOUR
AU - Friedrich, Christoph
AU - Blügel, Stefan
AU - Schindlmayr, Arno
ID - 22761
IS - 3
JF - Physical Review B
SN - 2469-9950
TI - Erratum: Efficient implementation of the GW approximation within the all-electron FLAPW method [Phys. Rev. B 81, 125102 (2010)]
VL - 104
ER -
TY - JOUR
AB - Uniaxial anisotropy in nonlinear birefringent crystals limits the efficiency of nonlinear optical interactions and breaks the spatial symmetry of light generated in the parametric down-conversion (PDC) process. Therefore, this effect is usually undesirable and must be compensated for. However, high gain may be used to overcome the destructive role of anisotropy in order to generate bright two-mode correlated twin-beams. In this work, we provide a rigorous theoretical description of the spatial properties of bright squeezed light in the presence of strong anisotropy. We investigate a single crystal and a system of two crystals with an air gap (corresponding to a nonlinear SU(1,1) interferometer) and demonstrate the generation of bright correlated twin-beams in such configurations at high gain due to anisotropy. We explore the mode structure of the generated light and show how anisotropy, together with crystal spacing, can be used for radiation shaping.
AU - Riabinin, M.
AU - Sharapova, Polina
AU - Meier, Torsten
ID - 37334
IS - 14
JF - Optics Express
KW - Atomic and Molecular Physics
KW - and Optics
SN - 1094-4087
TI - Bright correlated twin-beam generation and radiation shaping in high-gain parametric down-conversion with anisotropy
VL - 29
ER -
TY - JOUR
AU - Geraldi, Andrea
AU - De, Syamsundar
AU - Laneve, Alessandro
AU - Barkhofen, Sonja
AU - Sperling, Jan
AU - Mataloni, Paolo
AU - Silberhorn, Christine
ID - 26287
JF - Physical Review Research
SN - 2643-1564
TI - Transient subdiffusion via disordered quantum walks
ER -
TY - JOUR
AU - Tiedau, J.
AU - Engelkemeier, M.
AU - Brecht, Benjamin
AU - Sperling, Jan
AU - Silberhorn, Christine
ID - 21021
JF - Physical Review Letters
SN - 0031-9007
TI - Statistical Benchmarking of Scalable Photonic Quantum Systems
VL - 126
ER -
TY - JOUR
AU - Prasannan, Nidhin
AU - De, Syamsundar
AU - Barkhofen, Sonja
AU - Brecht, Benjamin
AU - Silberhorn, Christine
AU - Sperling, Jan
ID - 26286
JF - Physical Review A
SN - 2469-9926
TI - Experimental entanglement characterization of two-rebit states
VL - 103
ER -
TY - JOUR
AU - Köhnke, S.
AU - Agudelo, E.
AU - Schünemann, M.
AU - Schlettwein, O.
AU - Vogel, W.
AU - Sperling, Jan
AU - Hage, B.
ID - 26285
JF - Physical Review Letters
SN - 0031-9007
TI - Quantum Correlations beyond Entanglement and Discord
ER -
TY - JOUR
AB - 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.
AU - Bauch, David
AU - Heinze, Dirk Florian
AU - Förstner, Jens
AU - Jöns, Klaus
AU - Schumacher, Stefan
ID - 23816
JF - Physical Review B
KW - tet_topic_qd
SN - 2469-9950
TI - Ultrafast electric control of cavity mediated single-photon and photon-pair generation with semiconductor quantum dots
VL - 104
ER -
TY - JOUR
AB - 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.
AU - Wiebeler, Christian
AU - Vollbrecht, Joachim
AU - Neuba, Adam
AU - Kitzerow, Heinz-Siegfried
AU - Schumacher, Stefan
ID - 39653
IS - 1
JF - Scientific Reports
KW - Multidisciplinary
SN - 2045-2322
TI - Unraveling the electrochemical and spectroscopic properties of neutral and negatively charged perylene tetraethylesters
VL - 11
ER -
TY - JOUR
AU - Klement, Philip
AU - Dehnhardt, Natalie
AU - Dong, Chuan-Ding
AU - Dobener, Florian
AU - Bayliff, Samuel
AU - Winkler, Julius
AU - Hofmann, Detlev M.
AU - Klar, Peter J.
AU - Schumacher, Stefan
AU - Chatterjee, Sangam
AU - Heine, Johanna
ID - 40434
IS - 23
JF - Advanced Materials
KW - Mechanical Engineering
KW - Mechanics of Materials
KW - General Materials Science
SN - 0935-9648
TI - Atomically Thin Sheets of Lead‐Free 1D Hybrid Perovskites Feature Tunable White‐Light Emission from Self‐Trapped Excitons
VL - 33
ER -
TY - JOUR
AU - Barkhausen, Franziska
AU - Pukrop, Matthias
AU - Schumacher, Stefan
AU - Ma, Xuekai
ID - 21359
IS - 7
JF - Physical Review B
SN - 2469-9950
TI - Structuring coflowing and counterflowing currents of polariton condensates in concentric ring-shaped and elliptical potentials
VL - 103
ER -
TY - JOUR
AU - Franz, Martin
AU - Chandola, Sandhya
AU - Koy, Maximilian
AU - Zielinski, Robert
AU - Aldahhak, Hazem
AU - Das, Mowpriya
AU - Freitag, Matthias
AU - Gerstmann, Uwe
AU - Liebig, Denise
AU - Hoffmann, Adrian Karl
AU - Rosin, Maximilian
AU - Schmidt, Wolf Gero
AU - Hogan, Conor
AU - Glorius, Frank
AU - Esser, Norbert
AU - Dähne, Mario
ID - 24975
JF - Nature Chemistry
SN - 1755-4330
TI - Controlled growth of ordered monolayers of N-heterocyclic carbenes on silicon
ER -
TY - JOUR
AB - 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.
AU - Kozub, Agnieszka L.
AU - Schindlmayr, Arno
AU - Gerstmann, Uwe
AU - Schmidt, Wolf Gero
ID - 23418
JF - Physical Review B
SN - 2469-9950
TI - Polaronic enhancement of second-harmonic generation in lithium niobate
VL - 104
ER -
TY - CONF
AU - Rose, Hendrik
AU - Paul, Jagannath
AU - Wahlstrand, Jared K.
AU - Bristow, Alan D.
AU - Meier, Torsten
ED - Betz, Markus
ED - Elezzabi, Abdulhakem Y.
ID - 23475
T2 - Ultrafast Phenomena and Nanophotonics XXV
TI - Theoretical analysis and simulations of two-dimensional Fourier transform spectroscopy performed on exciton-polaritons of a quantum-well microcavity system
VL - 11684
ER -
TY - JOUR
AU - Krauss-Kodytek, L.
AU - Hannes, W.-R.
AU - Meier, Torsten
AU - Ruppert, C.
AU - Betz, M.
ID - 37333
IS - 8
JF - Physical Review B
SN - 2469-9950
TI - Nondegenerate two-photon absorption in ZnSe: Experiment and theory
VL - 104
ER -
TY - JOUR
AU - Riabinin, Matvei
AU - Sharapova, Polina
AU - Bartley, Tim
AU - Meier, Torsten
ID - 21547
IS - 4
JF - Journal of Physics Communications
SN - 2399-6528
TI - Generating two-mode squeezing with multimode measurement-induced nonlinearity
VL - 5
ER -
TY - JOUR
AU - Krauss-Kodytek, L.
AU - Hannes, Wolf-Rüdiger
AU - Meier, Torsten
AU - Ruppert, C.
AU - Betz, M.
ID - 23472
IS - 8
JF - Physical Review B
SN - 2469-9950
TI - Nondegenerate two-photon absorption in ZnSe: Experiment and theory
VL - 104
ER -