Abstract
The diffusion and the lifetime of excitons were determined via laser-induced gratings in high-quality GaAs/As multiple quantum wells. The diffusion is governed by the interaction of the excitons with the interface roughness and with acoustic phonons. The exciton scattering rate was compared with the dephasing rate observed in subsequently performed photon echo experiments. The influence of interface-roughness scattering on the dephasing was found to be weak and independent of temperature for this coherent process. The exciton-phonon coupling deduced from diffusion shows an excellent agreement with theory, whereas the dephasing rates determined in our work and former contributions were found to agree only roughly with theoretically calculated values.
- Received 30 November 1992
DOI:https://doi.org/10.1103/PhysRevB.47.6827
©1993 American Physical Society