Spin to charge conversion at Rashba-split SrTiO_{3} interfaces from resonant tunneling

Abstract

Spin-charge interconversion is a very active area of research in spintronics. Yet, the complex behavior of some of the most promising systems such as SrTiO_{3} (STO) interfaces is not fully understood. Here, on the basis of a 6-band k.p method combined with spin-resolved scattering theory, we give a theoretical demonstration of transverse spin-charge interconversion physics in STO Rashba interfaces. Calculations involve injection of spin current from a ferromagnetic contact by resonant tunneling into the native Rashba-split resonant levels of the STO triangular quantum well. We compute an asymmetric tunneling electronic transmission yielding a transverse charge current flowing in plane, with a dependence with gate voltage in a very good agreement with existing experimental data.