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Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Ultrafast dynamics of confined and localized excitons in low-dimensional semiconductors

J. M. Hvam, W. Langbein, Paola Borri

Published May 24, 1999• 0 citations
Publisher

Abstract

Coherent optical spectroscopy in the form of nonlinear transient four-wave mixing (TFWM) and linear resonant Rayleigh scattering (RRS) has been applied to investigate the exciton dynamics of low-dimensional semiconductor heterostructures. The dephasing times of excitons are determined from the decay of the spectrally resolved non- linear signal as a function of the delay between the incident pulses in a two-beam TFWM experiment, and from the real time analysis of single speckles in RRS experiments (pure dephasing). From the density- and temperature- dependence of the dephasing times the exciton-exciton and the exciton-phonon interactions are determined. The degree of coherence of the secondary emission is determined from the speckle analysis.

DOI
10.1117/12.349310

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