title: Theory of the magnetic and metal-insulator transitions in RNiO3 bulk and layered structures.
abstract: A slave rotor--Hartree-Fock formalism is presented for studying the properties of the p-d model describing perovskite transition metal oxides, and a flexible and efficient numerical formalism is developed for its solution. The methodology is shown to yield, within a unified formulation, the significant aspects of the rare-earth nickelate phase diagram, including the paramagnetic metal state observed for the LaNiO3 and the correct ground-state magnetic order of insulating compounds. It is then used to elucidate ground state changes occurring as morphology is varied from bulk to strained and unstrained thin-film form. For ultrathin films, epitaxial strain and charge transfer to the apical out-of-plane oxygen sites are shown to have significant impact on the phase diagram.
authors.affiliation: Department of Physics, Columbia University, 538 West 120th Street, New York, New York 10027, USA.
authors.forename: Bayo
authors.initials: B
authors.lastname: Lau
authors.affiliation: Department of Physics, Columbia University, 538 West 120th Street, New York, New York 10027, USA.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Millis