How close is LaOFeAs to Mott transition? A model Hamiltonian calculation within the Gutzwiller approximation

ORAL

Abstract

Using a five-band tight binding model for LaOFeAs we study the role of electron correlations on the low energy electronic structure. The phase boundaries between a metallic state and Mott insulating phases are determined as a function of Coulomb repulsion U and Hund's coupling J for a total number of six d-electrons. For realistic values of U and J LaOFeAs is found to be on the metallic side of the phase boundary. In addition we give a number of spectroscopic signatures that can be used to determine whether the electronic excitations of the metallic state are affected by the vicinity to a Mott transition. These results elucidate the role of strong electron correlations in FeAs-based systems.

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Authors

  • Yongxin Yao

    Membership Pending

  • J\"org Schmalian

    Ames Lab and Iowa State University, Ames Laboratory / Iowa State University, Iowa State University

  • Rafael Fernandes

    Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, Iowa State University

  • Cai-Zhuang Wang

    Ames Laboratory, U.S. Department of Energy, Iowa State University, Ames Laboratory, U.S. DOE and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA

  • Kai-ming Ho

    Department of Physics, Ames Laboratory, U.S. Department of Energy, Iowa State University, Ames Laboratory, U.S. DOE and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA