OPTICAL-PROPERTIES OF ULTRATHIN GAAS ALAS QUANTUM-WELL STRUCTURES WITH AN ELECTRIC-FIELD/

A theoretical study of the optical properties of GaAs/AlAs quantum wel l structures in the presence of an electric field is presented. In the first part of the article, interband transitions from the valence ban d to the conduction band are studied near the type-I to type-II transi tion point. In the second part, the effect of the electric field on in tersubband transitions within the conduction band is considered. The b and structure is calculated using a second-nearest-neighbor empirical sp(3) tight binding method including spin-orbit effects. Interband and intersubband transition energies, optical matrix elements, and absorp tion coefficients are given as functions of the electric field. It is shown that the optical properties of these structures can be modified significantly with field near the anticrossing point. (C) 1996 America n Institute of Physics.