Abstract
We report on the low temperature linearly and circularly polarized photoluminescence excitation spectra, and on the temporal dependence of the polarized PL in undoped GaAs/AlxGa1-xAs quantum wells (QW). The polarization excitation spectra Plin(El) and Pcir(El), El is the exciting (laser) energy, monitored at the upper energy part of the photoluminescence (PL) band show two bands that are attributed to the (e1:hh1)1S and (e1:hh1)2S exciton states. Plin(t) and Pcir(t) decay much faster than PL(t). These observations are explained by the recombination of delocalized excitons in the high energy side of the PL band. These excitons can move over large `islands' in the QW plane and have a defined K∥. They scatter between the islands and relax by emitting acoustic phonons within the islands where they recombine. The spectral shape of Plin and Pcir is thus determined by the exciton - LA phonon scattering rate and the polarization relaxation time dependences on K∥.
Original language | English (US) |
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Pages (from-to) | 179-182 |
Number of pages | 4 |
Journal | Journal De Physique. IV : JP |
Volume | 3 |
Issue number | 5 |
DOIs | |
State | Published - 1993 |
Externally published | Yes |
Event | Proceedings of the Third International Conference on Optics of Excitons in Confined Systems - Montpellier, Fr Duration: Aug 30 1993 → Sep 2 1993 |
All Science Journal Classification (ASJC) codes
- General Physics and Astronomy