Time resolved luminescence experiments performed on GaA1As-GaAs-A1As nonsymmetric modulation n-doped thick Quantum Wells show an atypical behaviour regarding similar but symmetric ( GaA1As-GaAs-GaA1As ) Quantum Wells. In the latter system the luminescence has the standard radiative lifetimes in the range reported in the literature. Much shorter lifetimes for nonsymmetric Quantum Wells are a clear indication that a non radiative mechanism is associated with AlAs- GaAs interface. The temperature dependence ofthe lifetime and magneto-optical experiments suggest the existence of a non-radiative level 5 meV above the third electric subband of the Quantum Wells. Transfer ofcharge from GaAs ( F point ) to AlAs ( X point ) is proposed as a mechanism to shorten the lifetime ofthe luminescence process in agreement with theoretical calculations. 1_

Date Published: 1 March 1991
PDF: 7 pages
Proc. SPIE 1361, Physical Concepts of Materials for Novel Optoelectronic Device Applications I: Materials Growth and Characterization, (1 March 1991);

Published in SPIE Proceedings Vol. 1361:
Physical Concepts of Materials for Novel Optoelectronic Device Applications I: Materials Growth and Characterization
Manijeh Razeghi, Editor(s)