Optical transitions between higher levels in a quantum well in an electric field

Abstract

Optical transition matrix elements for transitions between various levels in a semiconductor quantum well in an electric field are analysed. Transitions between lower levels, for which the transition matrix elements decrease monotonically with increasing field, and those between higher levels have qualitatively different behaviour. For transitions between levels with different indices, which are forbidden (opposite parity) or nearly forbidden (same parity) at zero field, the corresponding matrix elements achieve rather large extrema at high enough fields, and may give rise to a major proportion of the absorption for appropriate photon energies.