@article{13769, author = {{Schmidt, Wolf Gero and Briggs, E. L. and Bernholc, J. and Bechstedt, F.}}, issn = {{0163-1829}}, journal = {{Physical Review B}}, number = {{3}}, pages = {{2234--2239}}, title = {{{Structural fingerprints in the reflectance anisotropy spectra ofInP(001)(2×4)surfaces}}}, doi = {{10.1103/physrevb.59.2234}}, volume = {{59}}, year = {{1999}}, } @article{13767, author = {{Esser, N. and Schmidt, Wolf Gero and Bernholc, J. and Frisch, A. M. and Vogt, P. and Zorn, M. and Pristovsek, M. and Richter, W. and Bechstedt, F. and Hannappel, Th. and Visbeck, S.}}, issn = {{0734-211X}}, journal = {{Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures}}, number = {{4}}, title = {{{GaP(001) and InP(001): Reflectance anisotropy and surface geometry}}}, doi = {{10.1116/1.590810}}, volume = {{17}}, year = {{1999}}, } @article{13764, author = {{Bechstedt, F. and Adolph, B. and Schmidt, Wolf Gero}}, issn = {{0103-9733}}, journal = {{Brazilian Journal of Physics}}, number = {{4}}, title = {{{Ab initio calculation of linear and nonlinear optical properties of semiconductor structures}}}, doi = {{10.1590/s0103-97331999000400007}}, volume = {{29}}, year = {{1999}}, } @article{7694, author = {{Tscheuschner, Ralf D. and Hoch, Sascha and Leschinsky, Eva and Meier, Cedrik and Theis, Sabine and Wieck, Andreas D.}}, issn = {{0217-9792}}, journal = {{International Journal of Modern Physics B}}, number = {{11}}, pages = {{1147--1170}}, publisher = {{World Scientific Pub Co Pte Lt}}, title = {{{Robustness of the Quantum Hall Effect, Sample Size Versus Sample Topology, and Quality Control Management of III–V Molecular Beam Epitaxy}}}, doi = {{10.1142/s0217979298000636}}, volume = {{12}}, year = {{1998}}, } @inproceedings{43335, abstract = {{A microscopic many-body theory is presented which allows one to compute the linear and nonlinear optical properties of semiconductor superlattices in the presence of static and time-dependent electric fields applied in the growth direction. For static fields the Bloch-oscillation dynamics, the role of Coulomb effects, carrier relaxation, phonon scattering, and inter- and intraband polarization dephasing is analyzed. The observability of dynamic localization using optical spectroscopy is discussed for alternating applied fields.}}, author = {{Meier, Torsten and Je, K.-C and Rossi, F. and Hader, J. and Thomas, P. and Koch, S.W.}}, booktitle = {{Ultrafast Phenomena in Semiconductors II}}, pages = {{20--27}}, publisher = {{SPIE}}, title = {{{Coherent electric-field effects in semiconductors}}}, doi = {{10.1117/12.306150}}, volume = {{3277}}, year = {{1998}}, } @article{43338, abstract = {{A theory for four-wave-mixing signals from molecular aggregates, which includes effects of two-exciton states, static disorder, and coupling to a phonon bath with an arbitrary spectral density, is developed. The third-order polarization is rigorously partitioned into a coherent and a sequential contribution. The latter is given by a sum of an exciton-hopping and a ground state (bleaching) terms, both expressed using the doorway-window representation. Applications are made to photon-echo and pump-probe spectroscopies of the B850 system of the LH2 antenna in purple bacteria.}}, author = {{Meier, Torsten and Zhang, W.M. and Chernyak, V. and Mukamel, S.}}, journal = {{The Journal of chemical physics}}, number = {{18}}, pages = {{7763--7774}}, publisher = {{American Institute of Physics}}, title = {{{Exciton-Migration and Three-Pulse Femtosecond Optical Spectroscopies of Photosynthetic Antenna Complexes}}}, doi = {{10.1063/1.476212}}, volume = {{108}}, year = {{1998}}, } @article{43337, abstract = {{Femtosecond spectroscopies of chlorophyll dimers and the LH2 antenna complex are calculated using a theory that incorporates the effects of two–exciton states, static disorder and coupling of excitons to phonons with an arbitrary spectral density. Applications are made to pump–probe and echo peak–shift measurements in the B820 dimers, and to fluorescence depolarization in the B850 system of the LH2 antenna of purple bacteria.}}, author = {{Meier, Torsten and Zhang, W.M. and Chernyak, V. and Mukamel, S.}}, journal = {{Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences}}, number = {{1736}}, pages = {{405--419}}, publisher = {{The Royal Society}}, title = {{{Simulation of Three-Pulse-Echo and Fluorescence Depolarization in Photosynthetic Aggregates}}}, doi = {{10.1098/rsta.1998.0173}}, volume = {{356}}, year = {{1998}}, } @article{43336, abstract = {{We investigate the nonlinear dynamics of the composite absorber-cavity system by performing femtosecond time-resolved four-wave mixing experiments on a semiconductor microcavity. The nonlinear response exhibits an unexpected temporal behavior that distinctively differs from that of other multilevel systems. Accompanying model calculations show that the observed behavior is a direct consequence of the mixed electron-photon character of the absorber-cavity system.}}, author = {{Meier, Torsten and Koch, M. and Shah, J.}}, journal = {{Physical Review B}}, number = {{4}}, pages = {{2049--2052}}, publisher = {{American Physical Society}}, title = {{{Coupled absorber-cavity system: Observation of a characteristic nonlinear response}}}, doi = {{10.1103/PhysRevB.57.R2049}}, volume = {{57}}, year = {{1998}}, } @article{43339, author = {{Meier, Torsten and Thomas, P. and Koch, S.W.}}, journal = {{Physics of Low-Dimensional Structures (PLDS)}}, number = {{3-4}}, pages = {{1--44}}, title = {{{Coherent Effects in Photoexcited Semiconductor Superlattices with Electric Fields}}}, volume = {{1998}}, year = {{1998}}, } @article{43340, abstract = {{Femtosecond two beam and three beam ( ω1,ω1;ω2) four-wave mixing (FWM) experiments on GaAs quantum wells have been performed using two partially synchronized, independently tunable lasers with external jitter compensation. Heavy and light hole beatings are observed with these two mutually incoherent lasers. FWM signals are observed when ω2 is completely below the exciton energies, with no spectral overlap with the absorption profile. These off-resonant signals are stronger than the interband continuum signals for equivalent detunings.}}, author = {{Meier, Torsten and Kim, D.S. and Sohn, J.Y. and Yahng, J.S. and Ahn, Y. H. and Yee, K.J. and Yee, D.S. and Cho, Y.D. and Hong, S.C. and Kim, W.S. and Woo, J.C. and Koch, S.W. and Woo, D.H. and Kim, E. K. and Kim , S.H. and Kim, C.S.}}, journal = {{Physical review letters}}, number = {{21}}, pages = {{4803--4806}}, publisher = {{American Physical Society}}, title = {{{Femtosecond four-wave mixing experiments on GaAs quantum wells using two independently tunable lasers}}}, doi = {{10.1103/PhysRevLett.80.4803}}, volume = {{80}}, year = {{1998}}, } @article{43341, abstract = {{Closed Green-function expressions for the third-order response of semiconductors are derived by mapping the two-band model onto the much simpler molecular (Frenkel) Hamiltonian. The signatures of two-exciton resonances are incorporated through the exciton scattering matrix, totally avoiding the explicit calculation of two-exciton states. Exact expressions for the nonlinear optical response of two-dimensional semiconductor nanostructures in a strong perpendicular magnetic field are derived by truncating at the n=1 Landau level, and using the symmetry of the system and a group-theoretical analysis. We find that the nonlinear optical response depends crucially on asymmetries between particle-particle and particle-hole Coulomb interactions.}}, author = {{Meier, Torsten and Chernyak, V. and Yokojima, S. and Mukamel, S.}}, journal = {{Physical Review B}}, number = {{8}}, pages = {{4496--4516}}, publisher = {{American Physical Society}}, title = {{{Effective Frenkel Hamiltonian for optical nonlinearities in semiconductors: Application to magnetoexcitons}}}, doi = {{10.1103/PhysRevB.58.4496}}, volume = {{58}}, year = {{1998}}, } @article{43343, abstract = {{In his Comment on our work Glutsch raises, on the basis of a calculation for a dimerized three-dimensional superlattice, four points: (1) odd-parity excitons do not contribute to optical absorption, (2) there are no forbidden single-particle transitions, (3) there is a coupling of the e1-hh2 exciton (called ¯X in Ref. 1) to the underlying e1-hh1 continuum that leads to a Fano resonance, and (4) the extension of the exciton wave function is infinite in an all space directions rather than having a small extension. In this Reply these four points are addressed and it is shown that our previous conclusions remain valid.}}, author = {{Meier, Torsten and Bott, K. and Hader, J. and Brinkmann, D. and Koch, S.W. and Thomas, P.}}, journal = {{Physical Review B}}, number = {{23}}, publisher = {{American Physical Society}}, title = {{{Reply to Comment on "Odd-parity excitons in semiconductor superlattices"}}}, doi = {{10.1103/PhysRevB.58.15911}}, volume = {{58}}, year = {{1998}}, } @article{43344, abstract = {{Absorption and differential electroabsorption spectra of a GaInAs/InP superlattice in the regime of Wannier–Stark localization are compared with spectra derived from the Semiconductors Bloch Equations. The absorption is strongly underestimated for higher energies by the effective mass approximation but good agreement is achieved by using an energy dependent in-plane effective mass. No fitting parameters are used except for a phenomenological broadening. The lineshape of the field-modulated spectra is dominated by the strong field dependence of Wannier–Stark transitions and depends on the amplitude of the modulating field which should be kept small for best results. REFERENCES}}, author = {{Meier, Torsten and Thränhardt, A. and Kolbe, H.J. and Hader, J. and Weiser, G. and Koch, S.W.}}, journal = {{Applied Physics Letters}}, number = {{18}}, pages = {{2612--2614}}, publisher = {{American Institute of Physics}}, title = {{{Field-dependent absorption in superlattices: Comparison of theory and experiment}}}, doi = {{10.1063/1.122522}}, volume = {{73}}, year = {{1998}}, } @article{43342, abstract = {{The four-wave mixing (FWM) signal of a semiconductor superlattice with an external electric field is evaluated using the semiconductor Bloch equations. It is found that the FWM signal for a GaAs/AlGaAs-semiconductor superlattices with a lattice constant d has a deep valley when the electric field is around eF d = 1 meV. It is also found that the deep valley comes mainly from the broken inversion symmetry caused by the exteral electric field and that the field intensity determines the sign and the magnitude of the Coulomb-induced optical nonlinearities.}}, author = {{Meier, Torsten and Je, K.-C and Kim, Y. and Koch, S.W.}}, journal = {{Journal of the Korean Physical Society}}, number = {{4}}, pages = {{437--440}}, title = {{{Field-Induced Four-Wave Mixing Signal in Semiconductor Superlattices}}}, volume = {{32}}, year = {{1998}}, } @inproceedings{44274, abstract = {{Femtosecond four-wave mixing experiments on GaAs/AlGaAs quantum wells are performed with two independently tunable lasers. Many new results are found, including the heavy-hole-light-hole beating with these two mutually incoherent lasers.}}, author = {{Meier, Torsten and Yahng, J.S. and Ahn, Y. H. and Sohn, J.Y. and Koch, S.W. and Kim, D.S.}}, booktitle = {{Ultrafast Phenomena XI}}, isbn = {{10.1007/978-3-642-72289-9_70}}, location = {{Garmisch-Partenkirchen, Germany}}, pages = {{236--238}}, publisher = {{Springer, Berlin, Heidelberg}}, title = {{{Femtosecond Two Color Four-Wave Mixing Experiments on GaAs Quantum Wells Using Two Independently Tunable Lasers}}}, doi = {{10.1007/978-3-642-72289-9_70}}, year = {{1998}}, } @article{13773, author = {{Schmidt, Wolf Gero and Bechstedt, F. and Esser, N. and Pristovsek, M. and Schultz, Ch. and Richter, W.}}, issn = {{0163-1829}}, journal = {{Physical Review B}}, number = {{23}}, pages = {{14596--14599}}, title = {{{Atomic structure of InP(001)-(2×4): A dimer reconstruction}}}, doi = {{10.1103/physrevb.57.14596}}, volume = {{57}}, year = {{1998}}, } @article{13772, author = {{Schmidt, Wolf Gero and Bechstedt, F.}}, issn = {{0039-6028}}, journal = {{Surface Science}}, number = {{3}}, pages = {{474--484}}, title = {{{Geometry and electronic structure of InP(001)(2×4) reconstructions}}}, doi = {{10.1016/s0039-6028(98)00260-x}}, volume = {{409}}, year = {{1998}}, } @article{13771, author = {{Shkrebtii, A. I. and Esser, N. and Richter, W. and Schmidt, Wolf Gero and Bechstedt, F. and Fimland, B. O. and Kley, A. and Del Sole, R.}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, number = {{3}}, pages = {{721--724}}, title = {{{Reflectance Anisotropy of GaAs(100): Theory and Experiment}}}, doi = {{10.1103/physrevlett.81.721}}, volume = {{81}}, year = {{1998}}, } @article{13774, author = {{Schmidt, Wolf Gero and Käckell, P. and Bechstedt, F.}}, issn = {{0169-4332}}, journal = {{Applied Surface Science}}, pages = {{136--140}}, title = {{{In-induced (4 × 2) reconstructions of GaAs(001) surfaces}}}, doi = {{10.1016/s0169-4332(97)00510-2}}, volume = {{123-124}}, year = {{1998}}, } @article{43396, abstract = {{A real-space formulation of time-resolved fluorescence of molecular aggregates is developed using the one-exciton density matrix ρ(t) of the optically driven system. A direct relationship is established between the superradiance enhancement factor Ls and the exciton coherence size Lρ associated with the off-diagonal density matrix elements in the molecular representation. Various factors which affect the latter, including finite temperature, energetic disorder, coupling with phonons, and polaron formation are explored. The theory is applied for the interpretation of recent measurements in the B850 system of the LH2 photosynthetic complexes.}}, author = {{Meier, Torsten and Zhao, Y. and Chernyak, V. and Mukamel, S.}}, journal = {{The Journal of chemical physics}}, number = {{10}}, pages = {{3876--3893}}, publisher = {{American Institute of Physics}}, title = {{{Polarons, localization, and excitonic coherence in superradiance of biological antenna complexes}}}, doi = {{10.1063/1.474746}}, volume = {{107}}, year = {{1997}}, }