Spin to charge conversion at Rashba-split SrTiO3 interfaces from resonant tunneling

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 SrTiO3 (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.