@article{43300, abstract = {{The influence of coupling, correlation, and disorder on exciton and biexciton signatures is investigated using coherent excitation spectroscopy. Different biexciton-induced transitions of a single biexciton state are spectrally resolved. One of the transitions is found to be particularly sensitive to disorder. Mixed biexciton resonances, resulting from attractively interacting heavy and light hole exciton states, are identified. The observations are analyzed on the basis of microscopic model calculations.}}, author = {{Meier, Torsten and Finger, E. and Kraft, S.P. and Hofmann, M. and Koch, S.W. and Stolz, W. and Rühle, W.W.}}, journal = {{physica status solidi (b)}}, number = {{1}}, pages = {{424--434}}, publisher = {{WILEY‐VCH Verlag}}, title = {{{Coulomb correlations and biexciton signatures in coherent excitation spectroscopy of semiconductor quantum wells}}}, doi = {{10.1002/1521-3951(200211)234:1<424::AID-PSSB424>3.0.CO;2-V}}, volume = {{234}}, year = {{2002}}, } @inbook{43298, author = {{Meier, Torsten and Reichelt, Matthias and Schlichenmaier, C. and Siggelkow, S. and Thomas, P. and Koch, S.W. and Weiser, S. and Sieh, C.}}, booktitle = {{Germany NIC Series Vol. 9}}, editor = {{Rollnik, Horst and Wolf, Dietrich}}, isbn = {{3-00-009055-X}}, pages = {{ 315--324}}, publisher = {{John von Neumann Institute for Computing}}, title = {{{Many-Body Correlation Effects in Photoexcited Semiconductor Heterostructures}}}, year = {{2002}}, } @article{43299, abstract = {{A density-matrix theory for absorption changes in semiconductors induced by electron or hole occupations is outlined. Bound and unbound trions are included via four-point correlation functions representing electron–hole pair transitions in the presence of carrier populations. The spectra calculated for semiconductor nanorings show bleaching of the exciton resonance and induced absorption at energies corresponding to transitions to bound and unbound trion states. Without a magnetic field, induced absorption below the exciton line due to bound negatively (positively) charged trions appears when the two electrons (holes) of the trion are in different bands. A magnetic field introduces characteristic modifications of the spectra that can be attributed to the Aharonov–Bohm effect. It may lead to the formation of additional bound magneto-trion states.}}, author = {{Meier, Torsten and Thomas, P. and Koch, S.W. and Maschke, K.}}, journal = {{physica status solidi (b)}}, number = {{1}}, pages = {{283--293}}, publisher = {{WILEY‐VCH Verlag}}, title = {{{Signatures of trions in the optical spectra of doped semiconductor nanorings in a magnetic field}}}, doi = {{10.1002/1521-3951(200211)234:1<283::AID-PSSB283>3.0.CO;2-J}}, volume = {{234}}, year = {{2002}}, } @article{43301, author = {{Meier, Torsten and Koch, S.W.}}, journal = {{Physik Journal}}, number = {{12}}, pages = {{41--48}}, publisher = {{WILEY-VCH}}, title = {{{Optodynamik}}}, volume = {{1}}, year = {{2002}}, } @article{13745, author = {{Onida, G. and Schmidt, Wolf Gero and Pulci, O. and Palummo, M. and Marini, A. and Hogan, C. and Del Sole, R.}}, issn = {{0031-8965}}, journal = {{physica status solidi (a)}}, number = {{4}}, pages = {{1233--1242}}, title = {{{Theory for Modeling the Optical Properties of Surfaces}}}, doi = {{10.1002/1521-396x(200112)188:4<1233::aid-pssa1233>3.0.co;2-w}}, volume = {{188}}, year = {{2002}}, } @article{13755, author = {{Lu, Wenchang and Schmidt, Wolf Gero and Briggs, E. L. and Bernholc, J.}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, number = {{20}}, pages = {{4381--4384}}, title = {{{Optical Anisotropy of theSiC(001)-(3×2)Surface: Evidence for the Two-Adlayer Asymmetric-Dimer Model}}}, doi = {{10.1103/physrevlett.85.4381}}, volume = {{85}}, year = {{2002}}, } @article{13749, author = {{Paget, D. and Garreau, Y. and Sauvage, M. and Chiaradia, P. and Pinchaux, R. and Schmidt, Wolf Gero}}, issn = {{0163-1829}}, journal = {{Physical Review B}}, pages = {{161305(R)}}, title = {{{X-ray diffraction analysis of the gallium-rich surface of GaAs(001)}}}, doi = {{10.1103/physrevb.64.161305}}, volume = {{64}}, year = {{2002}}, } @article{13752, author = {{Hingerl, K and Balderas-Navarro, R.E and Bonanni, A and Tichopadek, P and Schmidt, Wolf Gero}}, issn = {{0169-4332}}, journal = {{Applied Surface Science}}, pages = {{769--776}}, title = {{{On the origin of resonance features in reflectance difference data of silicon}}}, doi = {{10.1016/s0169-4332(01)00114-3}}, volume = {{175-176}}, year = {{2002}}, } @article{13750, author = {{Pulci, O. and Lüdge, K. and Vogt, P. and Esser, N. and Schmidt, Wolf Gero and Richter, W. and Bechstedt, F.}}, issn = {{0927-0256}}, journal = {{Computational Materials Science}}, pages = {{32--37}}, title = {{{First-principles study of InP and GaP(001) surfaces}}}, doi = {{10.1016/s0927-0256(01)00161-6}}, year = {{2002}}, } @article{13754, author = {{Schmidt, Wolf Gero and Bechstedt, F. and Bernholc, J.}}, issn = {{0163-1829}}, journal = {{Physical Review B}}, pages = {{045322}}, title = {{{Terrace and step contributions to the optical anisotropy of Si(001) surfaces}}}, doi = {{10.1103/physrevb.63.045322}}, volume = {{63}}, year = {{2002}}, } @article{13736, author = {{Schmidt, Wolf Gero and Bechstedt, F. and Lu, W. and Bernholc, J.}}, issn = {{0163-1829}}, journal = {{Physical Review B}}, pages = {{0855334}}, title = {{{Interplay of surface reconstruction and surface electric fields in the optical anisotropy of GaAs(001)}}}, doi = {{10.1103/physrevb.66.085334}}, volume = {{66}}, year = {{2002}}, } @article{13741, author = {{Schmidt, Wolf Gero and Bechstedt, F. and Fleischer, K. and Cobet, C. and Esser, N. and Richter, W. and Bernholc, J. and Onida, G.}}, issn = {{0031-8965}}, journal = {{physica status solidi (a)}}, number = {{4}}, pages = {{1401--1409}}, title = {{{GaAs(001): Surface Structure and Optical Properties}}}, doi = {{10.1002/1521-396x(200112)188:4<1401::aid-pssa1401>3.0.co;2-1}}, volume = {{188}}, year = {{2002}}, } @article{13742, author = {{Bechstedt, F. and Schmidt, Wolf Gero and Hahn, P.H.}}, issn = {{0031-8965}}, journal = {{physica status solidi (a)}}, number = {{4}}, pages = {{1383--1392}}, title = {{{Towards a Complete Many-Body Description: Optical Response of Real Surfaces}}}, doi = {{10.1002/1521-396x(200112)188:4<1383::aid-pssa1383>3.0.co;2-g}}, volume = {{188}}, year = {{2002}}, } @article{13738, author = {{Schmidt, Wolf Gero and Bechstedt, F. and Bernholc, J.}}, issn = {{0169-4332}}, journal = {{Applied Surface Science}}, pages = {{264--268}}, title = {{{GaAs(001) surface reconstructions: geometries, chemical bonding and optical properties}}}, doi = {{10.1016/s0169-4332(01)00862-5}}, volume = {{190}}, year = {{2002}}, } @article{13740, author = {{Hahn, P. H. and Schmidt, Wolf Gero and Bechstedt, F.}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, number = {{1}}, title = {{{Bulk Excitonic Effects in Surface Optical Spectra}}}, doi = {{10.1103/physrevlett.88.016402}}, volume = {{88}}, year = {{2002}}, } @article{13739, author = {{Schmidt, Wolf Gero}}, issn = {{0947-8396}}, journal = {{Applied Physics A: Materials Science & Processing}}, pages = {{89--99}}, title = {{{III-V compound semiconductor (001) surfaces}}}, doi = {{10.1007/s003390101058}}, volume = {{75}}, year = {{2002}}, } @article{13737, author = {{Seino, K. and Schmidt, Wolf Gero and Bechstedt, F. and Bernholc, J.}}, issn = {{0039-6028}}, journal = {{Surface Science}}, pages = {{406--410}}, title = {{{Structure and energetics of Ga-rich GaAs() surfaces}}}, doi = {{10.1016/s0039-6028(02)01278-5}}, volume = {{507-510}}, year = {{2002}}, } @article{8767, author = {{Reuter, Dirk and Meier, Cedrik and Álvarez, M. A. Serrano and Wieck, A. D.}}, issn = {{0003-6951}}, journal = {{Applied Physics Letters}}, pages = {{377--379}}, title = {{{Increased thermal budget for selectively doped heterostructures by employing AlAs/GaAs superlattices}}}, doi = {{10.1063/1.1386618}}, volume = {{79}}, year = {{2001}}, } @inbook{43303, abstract = {{This chapter focuses on the carrier interaction effects—that is, the many-body Coulomb correlations and their influence on band-gap semiconductor optical nonlinearities. The near band-gap semiconductor response is determined by the optical interaction with the resonant or near resonant material polarization that may result in the excitation of carriers (electron–hole pairs) and/or transient coherent nonlinearities. The microscopic analysis of these effects requires the investigation of the relevant quasi-particles and their interactions. Whereas the basic occurrence of a blue shift can be motivated already based on a simple two-level model, a more detailed understanding of the optical Stark effect in semiconductors requires a microscopic modeling of the relevant bands as well as the inclusion of the many-body Coulomb interaction. Compensations among the first- and higher-order Coulomb terms at the spectral positions of the exciton are obtained in the differential absorption induced by incoherent occupations.}}, author = {{Meier, Torsten and Koch, S.W.}}, booktitle = {{Ultrafast Physical Processes in Semiconductors}}, editor = {{Tsen, K.T.}}, isbn = {{978-0-12-752176-3}}, pages = {{231--313}}, publisher = {{Elsevier}}, title = {{{Coulomb correlation signatures in the excitonic optical nonlinearities of semiconductors}}}, doi = {{10.1016/S0080-8784(01)80172-1}}, volume = {{67}}, year = {{2001}}, } @article{43307, abstract = {{The influence of fifth-order coherences on the spectrally resolved four-wave mixing response of predominantly homogeneously broadened quasi-two-dimensional excitons is studied. Fifth-order signatures are discussed as a function of spectral position and excitation polarization. An exciton–biexciton beating for positive delay times is the dominant effect, which is pronounced at the exciton–biexciton transition for collinearly polarized excitation and at the exciton transition for cross-linearly polarized excitation. For negative delay times and collinearly polarized excitation a pronounced exciton–biexciton beating at the exciton resonance is observed that is vanishing for long negative delays owing to the faster dephasing in the two-exciton continuum compared with the bound biexciton state. These results are in qualitative agreement with microscopic model calculations that include the coherent dynamics of one- and two-exciton resonances up to the fifth order in the optical field.}}, author = {{Meier, Torsten and Langbein, W. and Koch, S.W. and Hvam, J.M.}}, journal = {{Journal of the Optical Society of America B}}, number = {{9}}, pages = {{1318--1325}}, publisher = {{Optical Society of America}}, title = {{{Spectral signatures of χ(5) processes in four-wave mixing of homogeneously broadened excitons}}}, doi = {{10.1364/JOSAB.18.001318}}, volume = {{18}}, year = {{2001}}, }