Using a nonvariational method in k space, we study the effects of -X valley mixing on the structure of excitons in an asymmetric AlxGa1-xAs/AlAs/GaAs/ AlxGa1-xAs quantum well. The formulation of excitons in this system involves two complications due to -X mixing: the nonparabolic subband structures in the xy plane, and the Coulomb interaction between different electronic subbands. These effects lead to a set of two coupled integral equations. The eigenvalues and functions thus obtained are then used to compute the optical absorption spectra for various structures near the -X crossing.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics