Orientation dependence of subband structure and optical properties in GaAsAlGaAs quantum wells: [001], [111], [110] and [310] growth directions

Abstract

We calculate the valence subband dispersion in GaAsAl xGa 1−xAs quantum wells, with growth axes along the [001], [111], [110] and [310] directions, by solving the multiband effective mass equations for the four-component envelope function. Boundary conditions for conservation of probability current are given for each growth direction. The conduction band dispersion is obtained from an accurate expression for the bulk dispersion which includes the effects of anisotropy and nonparabolicity. We use the calculated dispersion to examine the dependence of optical interband transitions on both polarization and valence-subband mixing.