@article{3970, abstract = {{Optical experiments on second-harmonic generation from split-ring-resonator square arrays show a nonmonotonic dependence of the conversion efficiency on the lattice constant. This finding is interpreted in terms of a competition between dilution effects and linewidth or near-field changes due to interactions among the individual elements in the array.}}, author = {{Linden, S. and Niesler, F. B. P. and Förstner, Jens and Grynko, Yevgen and Meier, Torsten and Wegener, M.}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, keywords = {{tet_topic_shg, tet_topic_meta}}, number = {{1}}, publisher = {{American Physical Society (APS)}}, title = {{{Collective Effects in Second-Harmonic Generation from Split-Ring-Resonator Arrays}}}, doi = {{10.1103/physrevlett.109.015502}}, volume = {{109}}, year = {{2012}}, } @article{43200, abstract = {{A novel adaptive approach to compute the eigenenergies and eigenfunctions of the two-particle (electron-hole) Schrödinger equation including Coulomb attraction is presented. As an example, we analyze the energetically lowest exciton state of a thin one-dimensional semiconductor quantum wire in the presence of disorder which arises from the non-smooth interface between the wire and surrounding material. The eigenvalues of the corresponding Schrödinger equation, i.e., the one-dimensional exciton Wannier equation with disorder, correspond to the energies of excitons in the quantum wire. The wavefunctions, in turn, provide information on the optical properties of the wire. We reformulate the problem of two interacting particles that both can move in one dimension as a stationary eigenvalue problem with two spacial dimensions in an appropriate weak form whose bilinear form is arranged to be symmetric, continuous, and coercive. The disorder of the wire is modelled by adding a potential in the Hamiltonian which is generated by normally distributed random numbers. The numerical solution of this problem is based on adaptive wavelets. Our scheme allows for a convergence proof of the resulting scheme together with complexity estimates. Numerical examples demonstrate the behavior of the smallest eigenvalue, the ground state energies of the exciton, together with the eigenstates depending on the strength and spatial correlation of disorder.}}, author = {{Meier, Torsten and Mollet, Christian and Kunoth, Angela}}, journal = {{Communications in Computational Physics}}, number = {{1}}, pages = {{21--47}}, publisher = {{Cambridge University Press}}, title = {{{Excitonic Eigenstates of Disordered Semiconductor Quantum Wires: Adaptive Wavelet Computation of Eigenvalues for the Electron-Hole Schrödinger Equation}}}, doi = {{10.4208/cicp.081011.260712a}}, volume = {{14}}, year = {{2012}}, } @inproceedings{4312, abstract = {{The intensity dependence of optically-induced injection currents in semiconductor quantum wells is investigated numerically. Oscillatory behavior of the electron charge current transients as function of intensity and time is predicted and explained.}}, author = {{Pochwala, Michal and Duc, Huynh Thanh and Förstner, Jens and Meier, Torsten}}, booktitle = {{CLEO:2011 - Laser Applications to Photonic Applications}}, isbn = {{9781557529107}}, issn = {{2160-8989 }}, keywords = {{tet_topic_qw}}, location = {{Baltimore, Maryland (USA)}}, publisher = {{Optical Society of America}}, title = {{{Intensity dependence of optically-induced injection currents in semiconductor quantum wells}}}, doi = {{10.1364/qels.2011.qmk4}}, year = {{2011}}, } @inproceedings{4043, abstract = {{We present numerical results of the mutual coupling between photonic crystal cavities and semiconductor quantum dots. Normal mode splitting between a single cavity mode and a single quantum dot is shown under weak excitation, while under strong excitation Q‐factor dependent side bands appear, according to the AC‐Stark effect. Coupled photonic crystals, aligned parallel but displaced under a 30°‐angle for efficient coupling, show line splittings of all eigenmodes, if a single eigenmode is resonantly coupled to a single quantum dot. The mutual coupling of N resonant quantum dots to a single cavity mode results in a N−−√ scaling of the splitting, known from quantum optics, but corrected by the field amplitude fraction for not collocated quantum dots.}}, author = {{Declair, S. and Song, X. and Meier, Torsten and Förstner, Jens}}, booktitle = {{THE FOURTH INTERNATIONAL WORKSHOP 2011}}, keywords = {{tet_topic_phc, tet_topic_qd}}, location = {{Bad Honnef}}, number = {{123}}, pages = {{123--125}}, publisher = {{AIP}}, title = {{{Simulation of Mutual Coupling of Photonic Crystal Cavity Modes and Semiconductor Quantum Dots}}}, doi = {{10.1063/1.3644232}}, volume = {{1398}}, year = {{2011}}, } @article{44059, abstract = {{A novel adaptive wavelet based method is presented that allows us to compute eigenvalues and eigenvectors of the electronic Schrödinger equation. Our method outperforms direct discretization methods with equidistant grid spacings, in particular, for problems that involve several length scales. As an application we present numerical evaluations of the energetically lowest exciton states for ordered and disordered semiconductor quantum wires.}}, author = {{Meier, Torsten and Mollet, Christian and Kunoth, Angela}}, journal = {{AIP Conference Proceedings}}, number = {{1}}, pages = {{156--158}}, publisher = {{American Institute of Physics}}, title = {{{Wavelet‐Based Adaptive Computations of the Excitonic Eigenstates of Disordered Semiconductor Quantum Wires}}}, doi = {{10.1063/1.3644243}}, volume = {{1398}}, year = {{2011}}, } @inproceedings{4048, abstract = {{We present an ab-initio method for calculating nonlinear and nonlocal optical effects in metallic slabs with sub-wavelength thickness. We find a strong localization of the second-harmonic current at the metal-vacuum interface.}}, author = {{Wand, Mathias and Schindlmayr, Arno and Meier, Torsten and Förstner, Jens}}, booktitle = {{CLEO:2011 - Laser Applications to Photonic Applications }}, isbn = {{978-1-4577-1223-4}}, issn = {{2160-8989}}, keywords = {{tet_topic_shg}}, location = {{Baltimore, Maryland, United States}}, publisher = {{Optical Society of America}}, title = {{{Theoretical approach to the ultrafast nonlinear optical response of metal slabs}}}, doi = {{10.1364/CLEO_AT.2011.JTuI59}}, year = {{2011}}, } @article{43259, abstract = {{The extreme nonlinear terahertz response of initially unexcited intrinsic semiconductor nanostructures is studied theoretically by solving extended semiconductor Bloch equations numerically. The coupled dynamics of intraband acceleration and multiphoton interband transitions leads to high-harmonic generation up to several tens of the exciting terahertz frequency. It is shown that the actual cut-off frequency is determined by the band structure and not by the excitation strength.}}, author = {{Golde, D. and Kira, M. and Meier, Torsten and Koch, S.W.}}, journal = {{physica status solidi (b)}}, number = {{4}}, pages = {{863--866}}, publisher = {{WILEY‐VCH Verlag}}, title = {{{Microscopic theory of the extremely nonlinear terahertz response of semiconductors}}}, doi = {{10.1002/pssb.201000840}}, volume = {{248}}, year = {{2011}}, } @inproceedings{44060, abstract = {{In recent years, single-walled carbon nanotubes (SWCNTs) have received widespread attention due to their perfect quasi-one-dimensional structure and unique physical properties, as well as their potential for applications. In the present work, we calculate the band structure of SWCNTs using an atomistic tight-binding model including spin-orbit interaction. We combine this approach with a many-particle calculation of the nonlinear optical response using multi-band semiconductor Bloch equations. We show that, for SWCNTs lacking inversion symmetry, the intrinsic spin-orbit interaction can give rise to single-color photoinduced charge and spin currents. In particular, we study the influence of excitonic effects on these photoinduced currents and draw the analogy to recent investigations on single-color injection of photocurrents in semiconductor quantum wells.}}, author = {{Meier, Torsten and Liu, Hong and Duc, Huynh Thanh and Schumache, Stefan}}, booktitle = {{75. Annual meeting of the DPG and combined DPG Spring meeting}}, issn = {{0420-0195}}, location = {{Dresden, Germany}}, number = {{1}}, title = {{{Photocurrents in semiconductor carbon nanotubes with spin-orbit interaction}}}, volume = {{46}}, year = {{2011}}, } @inproceedings{44062, abstract = {{Optical two-dimensional Fourier transform spectroscopy has been used to study the properties of semiconductor nanostructures in four-wave-mixing like experiments. Applying a phenomenological level model, we numerically and analytically analyze the main features of excitonic and biexcitonic contributions in a semiconductor quantum well by solving the optical Bloch equations. The method is extended to three-dimensional Fourier transform spectroscopy to investigate a recent experiment.}}, author = {{Meier, Torsten and Wiebeler, Christian and Reichelt, Matthias}}, booktitle = {{ 75. Annual meeting of the DPG and combined DPG Spring meeting }}, issn = {{0420-0195}}, location = {{Dresden, Germany}}, number = {{1}}, title = {{{Analysis of multidimensional Fourier transform spectroscopy for semiconductors with a phenomenological level model}}}, volume = {{46}}, year = {{2011}}, } @inproceedings{44061, abstract = {{If a two-level system is excited with an intense light field of several times the Rabi frequency, the well-known Mollow triplets appear in the emitted radiation spectrum. We show that the pattern of the emission spectrum can be changed by using appropriately shaped laser pulses. The effect is also observable for a more realistic description of a semiconductor system.}}, author = {{Meier, Torsten and Reichelt, Matthias and Walther, Andrea}}, booktitle = {{75. Annual meeting of the DPG and combined DPG Spring meeting}}, issn = {{0420-0195}}, location = {{ Dresden, Germany}}, number = {{1}}, title = {{{Extreme nonlinear optics in semiconductors with shaped laser pulses}}}, volume = {{46}}, year = {{2011}}, } @inproceedings{4042, abstract = {{A simulation environment for metallic nanostructures based on the Discontinuous Galerkin Time Domain method is presented. It is used to model optical transmission by silver bi‐chiral plasmonic crystals. The results of simulations qualitatively and quantitavely agree with experimental measurements of transmitted circular polarization.}}, author = {{Grynko, Yevgen and Förstner, Jens and Meier, Torsten and Radke, André and Gissibl, Timo and Braun, Paul V. and Giessen, Harald}}, editor = {{Chigrin, Dmitry N.}}, keywords = {{tet_topic_meta}}, number = {{1}}, pages = {{76--78}}, publisher = {{AIP}}, title = {{{Application of the Discontinuous Galerkin Time Domain Method to the Optics of Bi-Chiral Plasmonic Crystals}}}, doi = {{10.1063/1.3644217}}, volume = {{1398}}, year = {{2011}}, } @article{13565, author = {{Müllegger, Stefan and Schöfberger, Wolfgang and Rashidi, Mohammad and Lengauer, Thomas and Klappenberger, Florian and Diller, Katharina and Kara, Kamuran and Barth, Johannes V. and Rauls, Eva and Schmidt, Wolf Gero and Koch, Reinhold}}, issn = {{1936-0851}}, journal = {{ACS Nano}}, number = {{8}}, pages = {{6480--6486}}, title = {{{Preserving Charge and Oxidation State of Au(III) Ions in an Agent-Functionalized Nanocrystal Model System}}}, doi = {{10.1021/nn201708c}}, volume = {{5}}, year = {{2011}}, } @article{13566, author = {{Hoehne, Felix and Lu, Jinming and Stegner, Andre R. and Stutzmann, Martin and Brandt, Martin S. and Rohrmüller, Martin and Schmidt, Wolf Gero and Gerstmann, Uwe}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, number = {{19}}, title = {{{Electrically Detected Electron-Spin-Echo Envelope Modulation: A Highly Sensitive Technique for Resolving Complex Interface Structures}}}, doi = {{10.1103/physrevlett.106.196101}}, volume = {{106}}, year = {{2011}}, } @article{13568, author = {{Mietze, C. and Landmann, M. and Rauls, E. and Machhadani, H. and Sakr, S. and Tchernycheva, M. and Julien, F. H. and Schmidt, Wolf Gero and Lischka, K. and As, Donat Josef}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{19}}, title = {{{Band offsets in cubic GaN/AlN superlattices}}}, doi = {{10.1103/physrevb.83.195301}}, volume = {{83}}, year = {{2011}}, } @article{13570, author = {{Müllegger, S. and Rashidi, M. and Lengauer, T. and Rauls, E. and Schmidt, Wolf Gero and Knör, G. and Schöfberger, W. and Koch, R.}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{16}}, title = {{{Asymmetric saddling of single porphyrin molecules on Au(111)}}}, doi = {{10.1103/physrevb.83.165416}}, volume = {{83}}, year = {{2011}}, } @article{13567, author = {{Konopka, A. and Greulich-Weber, S. and Dierolf, V. and Jiang, H.X. and Gerstmann, Uwe and Rauls, E. and Sanna, S. and Schmidt, Wolf Gero}}, issn = {{0925-3467}}, journal = {{Optical Materials}}, pages = {{1041--1044}}, title = {{{Microscopic structure and energy transfer of vacancy-related defect pairs with Erbium in wide-gap semiconductors}}}, doi = {{10.1016/j.optmat.2010.12.005}}, volume = {{33}}, year = {{2011}}, } @article{13571, author = {{Thierfelder, C. and Witte, M. and Blankenburg, S. and Rauls, E. and Schmidt, Wolf Gero}}, issn = {{0039-6028}}, journal = {{Surface Science}}, pages = {{746--749}}, title = {{{Methane adsorption on graphene from first principles including dispersion interaction}}}, doi = {{10.1016/j.susc.2011.01.012}}, volume = {{605}}, year = {{2011}}, } @article{13569, author = {{Favero, P.P. and Ferraz, A.C. and Schmidt, Wolf Gero and Miotto, R.}}, issn = {{0039-6028}}, journal = {{Surface Science}}, pages = {{824--830}}, title = {{{Driving forces for the adsorption of cyclopentene on InP(001)}}}, doi = {{10.1016/j.susc.2011.01.027}}, volume = {{605}}, year = {{2011}}, } @article{13563, author = {{Schmidt, Wolf Gero and Babilon, M. and Thierfelder, C. and Sanna, S. and Wippermann, S.}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{11}}, title = {{{Influence of Na adsorption on the quantum conductance and metal-insulator transition of the In-Si(111)(4×1)–(8×2) nanowire array}}}, doi = {{10.1103/physrevb.84.115416}}, volume = {{84}}, year = {{2011}}, } @article{13561, author = {{Berth, Gerhard and Hahn, Wjatscheslaw and Wiedemeier, Volker and Zrenner, Artur and Sanna, Simone and Schmidt, Wolf Gero}}, issn = {{0015-0193}}, journal = {{Ferroelectrics}}, pages = {{44--48}}, title = {{{Imaging of the Ferroelectric Domain Structures by Confocal Raman Spectroscopy}}}, doi = {{10.1080/00150193.2011.594774}}, volume = {{420}}, year = {{2011}}, }