title: Dynamical mean field theory of an effective three-band model for NaxCoO2.
abstract: We derive an effective Hamiltonian for highly correlated t_{2g} states centered at the Co sites of NaxCoO2. The essential ingredients of the model are an O mediated hopping, a trigonal crystal-field splitting, and on-site effective interactions derived from the exact solution of a multiorbital model in a CoO6 cluster, with parameters determined previously. The effective model is solved by dynamical mean field theory. We obtain a Fermi surface and electronic dispersion that agrees well with angle-resolved photoemission spectra. Our results also elucidate the origin of the "sinking pockets" in different doping regimes.
authors.affiliation: Laboratoire de Physique des Solides, Université Paris-Sud, CNRS UMR-8502, 91405 Orsay cedex, France.
authors.forename: A
authors.initials: A
authors.lastname: Bourgeois
authors.forename: A A
authors.initials: AA
authors.lastname: Aligia
authors.forename: M J
authors.initials: MJ
authors.lastname: Rozenberg