Electronic-structureinduced reconstruction and magnetic ordering at the LaAlO3|SrTiO3 interfaceZhicheng Zhong and Paul J. Kelly
Faculty of Science and Technology and MESA+ Institute for Nanotechnology, University of Twente P.O. Box 217, 7500 AE Enschede, The Netherlands
received on 27 August 2008; accepted in final form by E. Bertel on 1 September 2008; published October 2008
published online 10 September 2008
Using local density approximation (LDA) calculations we predict GdFeO3-like rotation of TiO6 octahedra at the n-type interface between LaAlO3 and SrTiO3. This results in a narrowing of the Ti d bandwidth by 1/3 so that LDA+U calculations predict an antiferromagnetic, charge- and spin-ordered ground state for very modest values of U. Recent experimental evidence for magnetic interface ordering may be understood in terms of the close proximity of an antiferromagnetic insulating ground state to a ferromagnetic metallic excited state.
75.70.Cn - Magnetic properties of interfaces (multilayers, superlattices, heterostructures).
73.20.-r - Electron states at surfaces and interfaces.
68.35.Ct - Interface structure and roughness.
© EPLA 2008