title: Ferromagnetism in itinerant two-dimensional t2g systems.
abstract: Motivated by the recent indications of ferromagnetism in transition metal oxide heterostructures, we propose a possible mechanism to generate ferromagnetism for itinerant t(2g) systems in two spatial dimensions that does not rely on the coupling between local moments and conduction electrons. We particularly emphasize the orbital nature of different bands and show that when the Fermi level lies near the bottom of the upper bands, a nonperturbative interaction effect due to the quasi-one-dimensional nature of the upper bands may drive a transition to a state in which the upper bands are ferromagnetically polarized. In the quasi-one-dimensional limit, the full thermodynamics may be obtained exactly. We discuss the connection between our mechanism with several itinerant t(2g) systems that may have ferromagnetic instabilities.
authors.affiliation: Department of Physics, University of Colorado, Boulder, Colorado 80309-0390, USA.
authors.forename: Gang
authors.initials: G
authors.lastname: Chen
authors.affiliation: Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106-4030, USA.
authors.forename: Leon
authors.initials: L
authors.lastname: Balents