Electroreflectance Spectra and Field-Induced Variation in Refractive Index of a GaAs/AlAs Quantum Well Structure at Room Temperature

Abstract

Observed electroreflectance spectra for a GaAs/AlAs quantum well structure show very clear exciton-induced features at room temperature. A maximum rate for the field-induced modulation of refractive index, Δ n / n / E in each quantum well is deduced to be 4%/10 5 V/cm at a photon energy close to the excitonic gap. Such a large variation in the refractiveindex is attributed to excitonic transitions.