title: Orbital order and possible superconductivity in LaNiO3/LaMO3 superlattices.
abstract: A hypothetical layered oxide La2NiMO6 where NiO2 and MO2 planes alternate along the c axis of ABO3 perovskite lattice is considered theoretically. Here, M denotes a trivalent cation Al, Ga,... such that MO2 planes are insulating and suppress the c-axis charge transfer. We predict that correlated eg electrons in the NiO2 planes develop a planar x2-y2 orbital order driven by the reduced dimensionality and further supported by epitaxial strain from the substrate. Low-energy electronic states can be mapped to a single-band t - t' - J model, suggesting favorable conditions for high-Tc superconductivity.
authors.affiliation: Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569 Stuttgart, Germany.
authors.forename: Jirí
authors.initials: J
authors.lastname: Chaloupka
authors.forename: Giniyat
authors.initials: G
authors.lastname: Khaliullin