1209.4705 (Zhicheng Zhong et al.)

Theory of spin-orbit coupling at LaAlO3/SrTiO3 interfaces and SrTiO3
surfaces    [PDF]

Zhicheng Zhong, Anna Toth, Karsten Held

A full theoretical understanding of the spin-orbit coupling (SOC) effects at LaAlO3/SrTiO3 interfaces and SrTiO3 surfaces is still needed. We perform first-principles density-functional-theory calculations and derive from these a simple tight-binding Hamiltonian, through a Wannier function projection and group theoretical analysis. We find striking differences to the standard Rashba theory for spin-orbit coupling in semiconductor heterostructures, because the relevant t2g orbitals are very different from nearly free electrons. The key ingredients to the spin splitting are the atomic SOC and the interface asymmetry, which enters via asymmetric t2g orbital lobes.

View original: http://arxiv.org/abs/1209.4705