Stark effect in strongly coupled quantum wells

Abstract

The energies and oscillator strengths of the excitonic transitions in a pair of strongly coupled quantum wells in the GaAs/${\mathrm{Al}}_{\mathrm{x}}$ ${\mathrm{Ga}}_{1\mathrm{-}\mathrm{x}}$As system have been experimentally investigated as a function of electric field and compared with an effective-mass calculation which neglects band mixing. Good agreement with experiment can be obtained by taking into account nonparabolicity in the light-hole bands. Although not readily evident in the field dependence of the excitonic transition energies, band mixing has a measurable effect on exciton linewidths. The optoelectronic device implications of the Stark effect observed in this system are briefly considered.