Quantum Monte Carlo study of a Z2 gauge theory containing phases with and without a Luttinger volume Fermi surface

ORAL

Abstract

We describe sign-problem-free quantum Monte Carlo simulations of a model of electrons, cα, at half-filling on the square lattice. The model is a Z2 gauge theory in which the cα are allowed to fractionalize into two partons carrying Z2 gauge charges: an `orthogonal’ fermion ψα carrying both the spin and the electromagnetic charge of the electron, and an Ising matter field. Among the phases found are two with no broken symmetries: (A) an orthogonal semi-metal, which has a Dirac spectrum of the ψα, and (B) a metal with a Luttinger volume Fermi surface of the cα.

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Presenters

  • Subir Sachdev

    Harvard University, Physics, Harvard University, Harvard Univ, Physics, Harvard Univ, Department of Physics, Harvard University

Authors

  • Fakher Assaad

    University of Wurzburg, Institut für Theoretische Physik und Astrophysik, Universität Würzburg, University Wuerzburg, Universität Würzburg, Physics, Universität Würzburg, University of Würzburg

  • Snir Gazit

    University of California, Berkeley, Department of Physics, University of California, Univ of California - Berkeley, Physics, University of California, Berkeley, Physics, Univ of California - Berkeley

  • Subir Sachdev

    Harvard University, Physics, Harvard University, Harvard Univ, Physics, Harvard Univ, Department of Physics, Harvard University

  • Ashvin Vishwanath

    Physics, Harvard University, Department of Physics, Harvard University, Harvard Univ, Caltech