TY - CHAP AB - We investigate the spatiotemporal characteristics of subpicosecond pulse propagation in the nonlinear defocusing regime below the band edge of bulk GaAs. We observe temporal and spatial pulse compression and instabilities. AU - Nielsen, N. C. AU - zu Höner Siederdissen, T. AU - Kuhl, J. AU - Schaarschmidt, M. AU - Förstner, Jens AU - Knorr, A. AU - Koch, S. W. AU - Giessen, H. ID - 4269 KW - tet_topic_polariton SN - 0172-6218 T2 - Springer Series in Chemical Physics TI - Temporal and Spatial Pulse Compression in a Nonlinear Defocusing Material ER - TY - JOUR AB - Using a fully quantized description of strongly confined electrons interacting with acoustic phonons and the photon field, the nonstationary resonance-fluorescence spectra of a semiconductor quantum dot are investigated. For excitation pulses with durations approaching typical electron-phonon scattering times, the virtual quantum processes yield an observable electron-phonon sideband broadening. AU - Ahn, K. J. AU - Förstner, Jens AU - Knorr, A. ID - 4260 IS - 15 JF - Physical Review B KW - tet_topic_qd SN - 1098-0121 TI - Resonance fluorescence of semiconductor quantum dots: Signatures of the electron-phonon interaction VL - 71 ER - TY - JOUR AB - Time-dependent two-photon photoemission spectra are used to resolve the femtosecond dynamics of hot electrons at the energetically lowest surface resonance of reconstructed InP(100). Two different cases are studied, where electrons either are lifted into the surface resonance via a direct optical transition or are captured from bulk states. These data are the first of this kind recorded with a time resolution below 70 fs. The microscopic analysis shows that electron-phonon scattering is a major mechanism for electron transfer between surface and bulk states. AU - Töben, L. AU - Gundlach, L. AU - Ernstorfer, R. AU - Eichberger, R. AU - Hannappel, T. AU - Willig, F. AU - Zeiser, A. AU - Förstner, Jens AU - Knorr, A. AU - Hahn, P. H. AU - Schmidt, W. G. ID - 4262 IS - 6 JF - Physical Review Letters SN - 0031-9007 TI - Femtosecond Transfer Dynamics of Photogenerated Electrons at a Surface Resonance of Reconstructed InP(100) VL - 94 ER - TY - JOUR AB - We demonstrate that the temporal pulse phase remains essentially unaltered before separate phase characteristics are developed when propagating high-intensity pulses coherently on the exciton resonance of an optically thick semiconductor. This behavior is a clear manifestation of self-induced transmission and pulse breakup into solitonlike pulses due to Rabi flopping of the carrier density. Experiments using a novel fast-scan cross-correlation frequency-resolved optical gating (XFROG) method are in good agreement with numerical calculations based on the semiconductor Bloch equations. AU - Nielsen, N. C. AU - zu Siederdissen, T. Höner AU - Kuhl, J. AU - Schaarschmidt, M. AU - Förstner, Jens AU - Knorr, A. AU - Giessen, H. ID - 4264 IS - 5 JF - Physical Review Letters KW - tet_topic_qd SN - 0031-9007 TI - Phase Evolution of Solitonlike Optical Pulses during Excitonic Rabi Flopping in a Semiconductor VL - 94 ER - TY - CONF AB - A theoretical description of ultrafast phonon induced electronic transport between surface and bulk states after optical excitation is presented. In particular, the influence of the electron transfer processes on two photon photo emission is evaluated. AU - Bucking, N. AU - Zeiser, A. AU - Förstner, Jens AU - Knorr, A. ID - 4258 SN - 1557527962 T2 - 2005 Quantum Electronics and Laser Science Conference TI - Kinetic theory of the electron transport in the two photon photo emission at semiconductor surfaces ER -