Eur. Phys. J. B 62, 257-261 (2008)
https://doi.org/10.1140/epjb/e2008-00161-6

Γ-X mixing in GaAs-Ga_1-xAl_xAs quantum wells under hydrostatic pressure

¹ Facultad de Ciencias, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, C.P. 62209, Morelos, Mexico
² Facultad de Educación, Universidad de Antioquia, AA, 1226 Medellín, Colombia
³ Instituto de Física, Universidad de Antioquia, AA, 1226 Medellín, Colombia
⁴ Instituto de Física, UNICAMP, CP 6165, 13083-970 Campinas -, SP, Brazil

Corresponding author: ^a cduque@fisica.udea.edu.co

Received: 12 October 2007
Published online: 19 April 2008

Abstract

The mixing between the Γ and X conduction-band valleys in GaAs-Ga_1-xAl_xAs quantum wells is investigated by using a phenomenological model which takes into account the effects of applied hydrostatic pressure. The dependencies of the variationally calculated photoluminescence peak-energy transitions on the applied hydrostatic pressure and quantum-well width are presented. A systematic study of the Γ-X mixing parameter is also reported. In particular, it is shown that the inclusion of the Γ-X mixing explains the non-linear behavior in the photoluminescence peak of confined exciton states that has been experimentally observed for pressures above 15 kbar in GaAs-Ga_1-xAl_xAs quantum wells.