Abstract
We have experimentally studied the time-evolution of the exciton population in a higher subband of GaAs quantum wells, below the free carrier continuum. The lifetime of the exciton formed by an electron of the lowest subband and a heavy hole of the second subband in GaAs quantum wells is determined by time-resolved luminescence as 130 ± 20 ps. This result is consistent with theoretical estimations of intersubband scattering by acoustic phonon emission. The exciton lifetime in the second heavy-hole subband is considerably longer than reported values of the recombination time in the lowest exciton state at k = 0. The excitons in the higher subband at k = 0 can be excited selectively without exciting the lower subband at k > 0. From these findings we conclude that subband transitions of excitons in quantum wells represent a new appealing concept for optically pumped coherent sources in the meV range.
Original language | English (US) |
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Pages (from-to) | 395-403 |
Number of pages | 9 |
Journal | Proceedings of SPIE - The International Society for Optical Engineering |
Volume | 1985 |
DOIs | |
State | Published - 1993 |
Externally published | Yes |
Event | Physical Concepts and Materials for Novel Optoelectronic Device Applications II 1993 - Trieste, Italy Duration: May 23 1993 → May 28 1993 |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Computer Science Applications
- Applied Mathematics
- Electrical and Electronic Engineering