Electron spin diffusion at the interface of multiferroic oxides

Abstract

We study the spin diffusion in a two-dimensional electron gas at the interface of oxide heterostructure LaAlO3/SrTiO3 grown on multiferroic TbMnO3 at 15 K by means of the kinetic spin Bloch equation approach. The spiral magnetic moments of Mn3+ in TbMnO 3 interact with the diffusing spins at the LaAlO3/ SrTiO3 interface via the Heisenberg exchange interaction. It is demonstrated that the spin diffusion length is always finite, despite the polarization direction of the injected spins. Our study also reveals the important role played by the Coulomb scattering, which can effectively suppress the spin diffusion. © 2011 American Physical Society.