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Updated: Jun 25, 2026

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Dynamical mean field theory of an effective three-band model for NaxCoO2
A Bourgeois1, A A Aligia, M J Rozenberg
1Laboratoire de Physique des Solides, Université Paris-Sud, CNRS UMR-8502, 91405 Orsay cedex, France.
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.
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