@article{13792, author = {{Schmidt, Wolf Gero and Bechstedt, F. and Srivastava, G.P.}}, issn = {{0039-6028}}, journal = {{Surface Science}}, pages = {{83--88}}, title = {{{Phonons at III–V (110) surfaces}}}, doi = {{10.1016/0039-6028(95)01095-5}}, volume = {{352-354}}, year = {{1996}}, } @article{13790, author = {{Schmidt, Wolf Gero and Käckell, P. and Bechstedt, F.}}, issn = {{0039-6028}}, journal = {{Surface Science}}, pages = {{545--549}}, title = {{{3d core-level shifts at}}}, doi = {{10.1016/0039-6028(96)00220-8}}, volume = {{357-358}}, year = {{1996}}, } @article{13782, author = {{Esser, N. and Shkrebtii, A. I. and Resch-Esser, U. and Springer, C. and Richter, W. and Schmidt, Wolf Gero and Bechstedt, F. and Del Sole, R.}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, number = {{21}}, pages = {{4402--4405}}, title = {{{Atomic Structure of the Sb-Stabilized GaAs(100)-(2×4) Surface}}}, doi = {{10.1103/physrevlett.77.4402}}, volume = {{77}}, year = {{1996}}, } @article{13784, author = {{Santos, Paulo V. and Koopmans, B. and Esser, N. and Schmidt, Wolf Gero and Bechstedt, F.}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, number = {{4}}, pages = {{759--762}}, title = {{{Optical Properties of Ordered As Layers on InP(110) Surfaces}}}, doi = {{10.1103/physrevlett.77.759}}, volume = {{77}}, year = {{1996}}, } @article{13783, author = {{Schmidt, Wolf Gero and Bechstedt, F.}}, issn = {{0163-1829}}, journal = {{Physical Review B}}, number = {{23}}, pages = {{16742--16748}}, title = {{{Geometry and electronic structure of GaAs(001)(2×4) reconstructions}}}, doi = {{10.1103/physrevb.54.16742}}, volume = {{54}}, year = {{1996}}, } @article{13786, author = {{Bechstedt, F and Schmidt, Wolf Gero and Scholze, A}}, issn = {{0295-5075}}, journal = {{Europhysics Letters (EPL)}}, number = {{8}}, pages = {{585--590}}, title = {{{Adatoms and vacancies on the diamond(111) surface}}}, doi = {{10.1209/epl/i1996-00155-0}}, volume = {{35}}, year = {{1996}}, } @article{13785, author = {{Schmidt, Wolf Gero and Bechstedt, F.}}, issn = {{0039-6028}}, journal = {{Surface Science}}, number = {{1}}, pages = {{L473--L477}}, title = {{{Atomic structures of GaAs(100)-(2 × 4) reconstructions}}}, doi = {{10.1016/0039-6028(96)00728-5}}, volume = {{360}}, year = {{1996}}, } @article{35381, author = {{Schmidt, Claudia and Rosen, M. E. and Caplan, D. F. and Pines, A. and Quinton, M. F.}}, issn = {{0022-3654}}, journal = {{The Journal of Physical Chemistry}}, keywords = {{Physical and Theoretical Chemistry, General Engineering}}, number = {{26}}, pages = {{10565--10572}}, publisher = {{American Chemical Society (ACS)}}, title = {{{Orientation and Motion of Tetrahydrofuran in Graphite Intercalation Compounds: Proton NMR Studies of Cs(THF)1.3C24 and K(THF)2.5C24}}}, doi = {{10.1021/j100026a020}}, volume = {{99}}, year = {{1995}}, } @article{35382, author = {{Lukaschek, Michail and Grabowski, David A. and Schmidt, Claudia}}, issn = {{0743-7463}}, journal = {{Langmuir}}, keywords = {{Electrochemistry, Spectroscopy, Surfaces and Interfaces, Condensed Matter Physics, General Materials Science}}, number = {{9}}, pages = {{3590--3594}}, publisher = {{American Chemical Society (ACS)}}, title = {{{Shear-Induced Alignment of a Hexagonal Lyotropic Liquid Crystal as Studied by Rheo-NMR}}}, doi = {{10.1021/la00009a050}}, volume = {{11}}, year = {{1995}}, } @article{35380, author = {{Fischer, Peter and Schmidt, Claudia and Finkelmann, Heino}}, issn = {{1022-1336}}, journal = {{Macromolecular Rapid Communications}}, keywords = {{Materials Chemistry, Polymers and Plastics, Organic Chemistry}}, number = {{6}}, pages = {{435--447}}, publisher = {{Wiley}}, title = {{{Amphiphilic liquid-crystalline networks — phase behavior and alignment by mechanical fields}}}, doi = {{10.1002/marc.1995.030160605}}, volume = {{16}}, year = {{1995}}, } @article{27953, author = {{Walther, J. and Bigga, Regine and Bischof, H.}}, journal = {{Sonderpädagogik }}, pages = {{4--22}}, title = {{{Computergestützte Intervention bei Rechtschreibschwäche: Effekte eines kognitions- und lernpsychologisch orientierten Trainingsprogramms auf Morphembasis bei sehr schwachen Sonderschülern.}}}, volume = {{1}}, year = {{1995}}, } @article{40315, abstract = {{ Most electrooptic effects in liquid crystals require a uniform orientation of the director at the glass substrates. A new method to produce suitable alignment layers is based on the creation of anisotropic polymer films by photopolymerization with linearly polarized light. In the present paper we report on measurements of the anchoring strength of these photo-induced anisotropic films. Using a wedge-cell technique, we find an azimuthal anchoring energy of W ϕ≈2.3·10-6 J/m2. }}, author = {{Vorflusev, Valery P. and Kitzerow, Heinz-Siegfried and Chigrinov, Vladimir G.}}, issn = {{0021-4922}}, journal = {{Japanese Journal of Applied Physics}}, keywords = {{General Physics and Astronomy, General Engineering}}, number = {{9A}}, publisher = {{IOP Publishing}}, title = {{{Azimuthal Anchoring Energy in Photoinduced Anisotropic Films}}}, doi = {{10.1143/jjap.34.l1137}}, volume = {{34}}, year = {{1995}}, } @article{43578, abstract = {{Coherent effects are analyzed that are induced by homogeneous electric fields in photoexcited semiconductors. Extended semiconductor Bloch equations are presented, which include the applied electric field, in addition to the many-body Coulomb contributions in the time-dependent Hartree-Fock approximation. These equations are solved for a one-dimensional tight-binding model of a semiconductor superlattice. Linear and nonlinear optical signals associated with the coherent field-induced effects are calculated. For the case of a static electric field, the influence of the Coulomb interaction, which is treated on the Hartree-Fock level for a contact potential approximation, on the Bloch oscillations, and on their counterpart in the frequency domain, the Wannier-Stark-ladder, is analyzed. For a time-dependent electric field, dynamic localization, i.e., the localization of electrons due to an oscillating electric field, is analyzed. It is predicted that the dynamic localization should be observable in semiconductor superlattices even in the presence of Coulomb interaction.}}, author = {{Meier, Torsten and von Plessen, G. and Thomas, P. and Koch, S.W.}}, journal = {{Physical Review B}}, number = {{20}}, pages = {{14490--14497}}, publisher = {{American Physical Society}}, title = {{{Coherent effects induced by static and time-dependent electric fields in semiconductors}}}, doi = {{10.1103/PhysRevB.51.14490}}, volume = {{51}}, year = {{1995}}, } @article{43586, abstract = {{We report results on selection rules and polarization conditions for quantum beating between light hole and heavy hole excitons in GaAs quantum wells. The measurements were conducted using time-integrated degenerate-four-wave-mixing in a three-pulse configuration. By choosing particular polarization configurations of the ultrashort optical pulses exciting heavy and light hole excitons simultaneously, degenerate four-wave-mixing signals show either quantum beating or no modulation at all. The experiments are analyzed using a model that takes into account exciton/exciton interaction.}}, author = {{Meier, Torsten and Smith, G.O. and Mayer, E.J. and Heuckeroth, V. and Kuhl, J. and Bott, K. and Schulze, A. and Bennhardt, D. and Koch, S.W. and Thomas, P. and Hey, R. and Ploog, K.}}, journal = {{Solid state communications}}, number = {{5}}, pages = {{373--377}}, publisher = {{Pergamon}}, title = {{{Polarization selection rules for quantum beating between light-and heavy-hole excitons in GaAs quantum wells}}}, doi = {{10.1016/0038-1098(95)00052-6}}, volume = {{94}}, year = {{1995}}, } @article{43590, abstract = {{The effective dimensionality of excitons can be drastically changed by applying an alternating electric field. On the basis of a full three-dimensional description of both coherent and incoherent phenomena in anisotropic structures it is found that appropriate applied oscillating fields change the exciton wave function from anisotropic three dimensional to basically two dimensional. This effective-dimension change is caused by dynamic localization which leads to an increase of the exciton binding energy and of the corresponding oscillator strength.}}, author = {{Meier, Torsten and Rossi, F. and Thomas, P. and Koch, S.W.}}, journal = {{Physical review letters}}, number = {{13}}, pages = {{2558--2561}}, publisher = {{American Physical Society}}, title = {{{Dynamic Localization in Anisotropic Coulomb Systems: Field induced Crossover of the Exciton Dimension}}}, doi = {{10.1103/PhysRevLett.75.2558}}, volume = {{75}}, year = {{1995}}, } @article{43591, abstract = {{Quasiequilibrium nonlinear optical absorption spectra are computed for semiconductor superlattices. The theory generalizes the semiconductor Bloch equations to describe anisotropic structures. The equation for the interband polarization is solved numerically and the carrier‐density dependent optical nonlinearities are computed. Starting from excitonic absorption, with increasing density exciton saturation and the development of gain is observed. The dependence of the gain spectra on structural parameters of the superlattice is discussed.}}, author = {{Meier, Torsten and Je, K.-C and Rossi, F. and Koch, S.W.}}, journal = {{Applied physics letters}}, number = {{20}}, pages = {{2978--2980}}, publisher = {{American Institute of Physics}}, title = {{{Theory of quasi-equilibrium nonlinear optical absorption in semiconductor superlattices}}}, doi = {{10.1063/1.114831}}, volume = {{67}}, year = {{1995}}, } @article{43589, author = {{Meier, Torsten and Kuhl, J. and Mayer, E.J. and Smith, G.O. and Bott, K. and Schulze, A. and Heuckeroth, V. and Heller, O. and Cundiff, S.T. and Bennhardt, D. and Koch, S.W. and Thomas, P. and Hey, R. and Ploog, K.}}, journal = {{Laser Physics}}, number = {{3}}, pages = {{616--620}}, publisher = {{INTERPERIODICA}}, title = {{{Transient degenerate four-wave-mixing on excitons in GaAs quantum wells}}}, volume = {{5}}, year = {{1995}}, } @inproceedings{43604, author = {{Meier, Torsten and Kuhl, J. and Mayer, E.J. and Smith, G.O. and Schulze, A. and Bennhardt, D. and Koch, S.W. and Thomas, P. and Hey, R. and Ploog, K.}}, booktitle = {{Proceedings of the 22nd International Conference on the Physics of Semiconductors ICPS}}, editor = {{Lockwood, D.J.}}, location = {{Vancouver, Canada}}, pages = {{1776--1779}}, publisher = {{World Scientific}}, title = {{{Biexciton Contributions to the Excitonic Nonlinearity in GaAs Quantum Wells}}}, year = {{1995}}, } @inproceedings{43451, author = {{Meier, Torsten and Feldmann, J. and Koch, M. and von Plessen, G. and Stolz, W. and Thomas, P. and Göbel, E.O.}}, booktitle = {{Proceedings of the 22nd International Conference on the Physics of Semiconductors ICPS}}, editor = {{Lockwood, D.J.}}, location = {{Vancouver, Canada}}, pages = {{1296--1303}}, publisher = {{World Scientific}}, title = {{{Coherent dynamics of exciton wave packets in quantum wells and superlattices}}}, year = {{1995}}, } @article{43452, abstract = {{We report time-resolved degenerate four-wave-mixing experiments on a high-quality single GaAs quantum well. The signals for parallel and cross-polarized exciting pulses show pronounced quantum beats with different frequencies corresponding to the heavy/light-hole splitting and the biexciton binding energy, respectively. Comparison of the experimental data with solutions of the optical Bloch equations for a phenomenological model system shows that these features result from strong contributions of the biexcitonic state. The importance of biexcitons to the nonlinear coherent response of the two-dimension exciton is further confirmed by the frequency dependence of the time-integrated four-wave-mixing signal amplitudes measured for the two polarization geometries.}}, author = {{Meier, Torsten and Mayer, E.J. and Smith, G.O. and Heuckeroth, V. and Kuhl, J. and Bott, K. and Schulze, A. and Koch, S.W. and Thomas, P. and Hey, R. and Ploog, K.}}, journal = {{Physical Review B}}, number = {{16}}, pages = {{10909--10914}}, publisher = {{American Physical Society}}, title = {{{Polarization dependence of beating phenomena at the energetically lowest exciton transition in GaAs quantum wells}}}, doi = {{10.1103/PhysRevB.51.10909}}, volume = {{51}}, year = {{1995}}, }