Termination control of electronic phases in oxide thin films and interfaces: LaAlO3/SrTiO3(001)

Abstract

A wealth of intriguing properties emerge in the seemingly simple system composed of the band insulators LaAlO3 and SrTiO3 such as a two-dimensional electron gas, superconductivity and magnetism. In this paper we review the current insight obtained from first principles calculations on the mechanisms governing the behavior of thin LaAlO3 films on SrTiO3(001). In particular, we explore the strong dependence of the electronic properties on the surface and interface termination, the finite film thickness, lattice polarization and defects. A further aspect that is addressed is how the electronic behavior and functionality can be tuned by a SrTiO3 capping layer, adsorbates and metallic contacts. Lastly, we discuss recent reports on the coexistence of magnetism and superconductivity in this system for what they might imply about the electronic structure of this system.