| Full text | |
| Author(s): |
Lourenco, S. A.
[1]
;
Teodoro, M. D.
[2]
;
Gonzalez-Borrero, P. P.
[3]
;
Dias, I. F. L.
[2]
;
Duarte, J. L.
[2]
;
Marega, Jr., E.
[4]
;
Salamo, G. J.
[5]
Total Authors: 7
|
| Affiliation: | [1] Univ Tecnol Federal Parana, BR-86036370 Londrina, PR - Brazil
[2] Univ Estadual Londrina, Dept Fis, BR-86051970 Londrina, PR - Brazil
[3] Univ Estadual Centro Oeste, Dept Fis, BR-85040080 Guarapuava, PR - Brazil
[4] Univ Sao Paulo, Inst Fis Sao Carlos, BR-13560970 Sao Carlos, SP - Brazil
[5] Univ Arkansas, Arkansas Inst Nanoscale Mat Sci & Engn, Fayetteville, AR 72701 - USA
Total Affiliations: 5
|
| Document type: | Journal article |
| Source: | PHYSICA B-CONDENSED MATTER; v. 407, n. 12, p. 2131-2135, JUN 15 2012. |
| Web of Science Citations: | 4 |
| Abstract | |
The competition between confinement potential fluctuations and band-gap renormalization (BGR) in GaAs/AlxGa1-xAs quantum wells grown on {[}1 0 0] and {[}3 1 1]A GaAs substrates is evaluated. The results clearly demonstrate the coexistence of the band-tail states filling related to potential fluctuations and the band-gap renormalization caused by an increase in the density of photogenerated carriers during the photoluminescence (PL) experiments. Both phenomena have strong influence on temperature dependence of the PL-peak energy (E-PL(T)). As the photon density increases, the E-PL can shift to either higher or lower energies, depending on the sample temperature. The temperature at which the displacement changes from a blueshift to a redshift is governed by the magnitude of the potential fluctuations and by the variation of BGR with excitation density. A simple band-tail model with a Gaussian-like distribution of the density of state was used to describe the competition between the band-tail filling and the BGR effects on E-PL(T). (C) 2012 Elsevier B.V. All rights reserved. (AU) | |