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.

*This research was supported by the Ames Laboratory, operated for the U.S. Department of Energy by Iowa State University under Contract No. DE-AC02-07CH11358.

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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