Far infrared optical properties of parallel quantum well wires with short lateral periods

Abstract

The optical properties are investigated numerically in the far infrared (FIR) region for the GaAs AlAs parallel quantum well wires (PQWWs) with short lateral periods produced by deposition of GaAs and AlAs fractional layers on (001) vicinal GaAs substrates. Calculations are carried out for the refractive indexes and optical absorption coefficients with and without the inclusion of electron interactions to find out the effects of intersubband plasmons on the FIR optical properties of PQWWs. As the lateral periods of PQWWs increase from 10 to 30 nm, their FIR optical properties change from the behaviour dominated by single electron transitions between conduction subbands to that dominated by intersubband plasmon excitations. Strong and sharp peaks in the optical absorption coefficients and large variations of the refractive indexes as functions of the frequencies of the incident light are predicted in the FIR region.