Spin accumulation from interlayer scattering in semiconductor bilayers

Abstract

Electrons in double-layer semiconductor heterostructures experience two types of spin- orbit interaction: one arises within each layer from the lack of bulk inversion symmetry and/or externally applied electric fields; the other arises from the electric field created by electron density fluctuations in the other layer. We show how these two interactions, acting in a concerted manner, produce spin accumulation in one layer when a current is driven in the other. This accumulation has the same temperature dependence (~T^2) as the recently described spin Hall drag accumulation, but it is parametrically stronger in the clean limit.