Infrared optical absorptions in corrugated lateral surface superlattices

The optical properties are investigated numerically in infrared (IR) regions for GaAs/AlAs corrugated lateral surface superlattices (CLSSLs) with short lateral periods. The calculations are carried out for refractive indexes and optical absorption coefficients with and without inclusion of electron interactions in an attempt to study the effects of intersubband plasmons on the IR optical properties of CLSSLs. As lateral periods of CLSSLs increase from 10 nm to 30 nm, their IR optical properties change from the behavior dominated by single electron transitions between conduction subbands to those dominated by intersubband plasmon excitations. Strong and sharp peaks in the optical absorption coefficients, large variations of the refractive indexes and strong anisotropic optical properties of CLSSLs are predicted in IR regions.