title: Orbital-selective Mott transition out of band degeneracy lifting.
abstract: We outline a general mechanism for orbital-selective Mott transition, the coexistence of both itinerant and localized conduction electrons, and show how it can take place in a wide range of realistic situations, even for bands of identical width and correlation, provided a crystal field splits the energy levels in manifolds with different degeneracies and the exchange coupling is large enough to reduce orbital fluctuations. The mechanism relies on the different kinetic energy in manifolds with different degeneracy. This phase has Curie-Weiss susceptibility and non-Fermi-liquid behavior, which disappear at a critical doping, all of which is reminiscent of the physics of the pnictides.
authors.affiliation: Department of Physics and Center for Materials Theory, Rutgers University, Piscataway New Jersey 08854, USA.
authors.forename: Luca
authors.initials: L
authors.lastname: de' Medici
authors.forename: S R
authors.initials: SR
authors.lastname: Hassan
authors.forename: Massimo
authors.initials: M
authors.lastname: Capone
authors.forename: Xi
authors.initials: X
authors.lastname: Dai