2D Electron Gas with 100% Spin‐Polarization in the (LaMnO₃)₂/(SrTiO₃)₂ Superlattice under Uniaxial Strain

Abstract

By first‐principles calculations we investigate the structural, electronic, and magnetic properties of the (LaMnO 3 ) 2 /(SrTiO 3 ) 2 superlattice. We find that a monoclinic C 2h symmetry is energetically favorable and that the spins order ferromagnetically. Under both compressive and tensile uniaxial strain the electronic structure of the superlattice shows a half‐metallic character. In particular, a fully spin‐polarized two‐dimensional electron gas, which traces back to the Ti 3d xy orbitals, is achieved under compressive uniaxial strain.