INFLUENCE OF THE CORRUGATION ON THE OPTICAL-PROPERTIES OF (113)ORIENTED GAAS ALAS SUPERLATTICES/

We report on the influence of the interface corrugation in (113)-grown GaAs/ALAs superlattices on their band-edge optical properties. We cal culate the subband dispersions and the optical anisotropies in a six-b and k.p formalism. The dominating contribution to the optical anisotro pies is found to be due to the intrinsic properties of the valence ban d structure. The corrugation modifies the density of states only sligh tly, giving no evidence of a quantum-wire behaviour. A comparison betw een the calculated and experimental optical anisotropy gives an upper limit for the corrugation height of 2 monolayers. The corrugation lead s to an anisotropic interface disorder, which gives rise to an enhance d anisotropy of localized type-I states at the band edge.