ABSTRACT
A brief review is given of the interface matrix giving boundary conditions for envelope functions at heterointerfaces. The envelope function approximation works reasonably well for connection of envelopes between Γ valley conduction band minima in III-V semiconductors. Mixing between Γ and X conduction-band valleys can be successfully described by a 6 x 6 interface matrix. An even-odd oscillation of the optical intensity as a function of the monolayer number for short-period GaAs/AlAs superlattices with lower X states is destroyed almost completely in the presence of interface fluctuations.
