Interface roughness scattering in semiconducting and semimetallic InAs-Ga1−<i>x</i>In<i>x</i>Sb superlattices

Abstract

An analysis of magnetotransport results for InAs-Ga1−xInxSb superlattices with a range of layer thicknesses demonstrates that interface roughness scattering dominates the electron mobility under most conditions of interest for infrared detector applications. However, the dependence on well thickness is much weaker than the d16 relation observed in other systems with thicker barriers, which is consistent with predictions based on the sensitivity of the energy levels to roughness fluctuations. Theory also correctly predicts an abrupt mobility decrease at the semiconductor-to-semimetal transition point, as well as the coexistence of two electron species in semimetallic samples.