Hole mixing at GaAs/AlAs(001) interfaces under normal incidence

摘要

The reduced point symmetry of a zinc-blende-based (001) interface allows mixing between heavy-and light-hole states even under normal incidence. We have generalized the envelope function approximation to take into account such a mixing by including off-diagonal terms into bound-ary conditions for the envelopes. For the first time, a tight-binding model has been used to relate the microscopic parameters with coefficients in the boundary conditions for the hole envelope function. The GAMMA -point interband matrix elements in GaAs/AlAs(001) multilayered structures have been calculated and the results have been compared with those obtained by microscopic-tight-binding calculations.