Inducing topological superconductivity at the LaAlO3/SrTiO3 interface

Abstract

The discovery of superconductivity in the two-dimensional electron gas at the interface between two band insulators SrTiO3 and LaAlO3 has opened up possibilities for novel physics. We show that due to the presence of Rashba spin-orbit interaction at the interface, a topological superconductivity can be induced by applying a magnetic field perpendicular to the interface plane even in the presence of the intrinsic in-plane magnetization. The inplane magnetization favours a finite momentum pairing of electrons and therefore weakens the topological superconducting phase. We show that the tunable Rashba spin-orbit interaction can help in stabilizing the topological superconducting state against the deleterious in-plane magnetization.