DIELECTRIC-PROPERTIES OF NONSQUARE ALGAAS/GAAS SINGLE QUANTUM-WELLS AT PHOTON ENERGIES BELOW THE BAND-GAP

The complex dielectric function of square and hyperbolic AlGaAs/GaAs single quantum wells have been calculated to predict the refractive index differences at photon energies below the band gap. The results show that, at these photon energies, the refractive index of a single hyperbolic quantum well exceeds that of the as-grown square quantum well during the initial stages of disordering, after which it decreases with increasing disorder. These results also predict the onset of antiguiding in multiple quantum well waveguides, which has been observed previously.