Dual fermion dynamical cluster approach for strongly correlated systems

ORAL

Abstract

A multi-scale many-body approach is developed for strongly-correlated electron systems by combining the dynamical cluster approximation (DCA) and the recently introduced dual fermion formalism. This approach systematically incorporates non-local corrections to the DCA by employing an exact mapping from a real lattice to a DCA cluster of linear size Lc embedded in a dual fermion lattice. The Green function in the dual space serves as a small parameter enabling the use of a diagrammatic perturbation calculation on the dual fermion lattice. For example, the dual fermion self-energy calculated with simple second-order perturbation theory scales as ${\cal{O}}(1/L_c^3)$. We demonstrate the effectiveness of the approach by applying it to the 2D Hubbard model.

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Authors

  • Shuxiang Yang

    Louisiana State University, Department of Physics and Astronomy, Louisiana State University, Department of Physics \& Astronomy, Louisiana State University

  • Herbert Fotso

    Georgetown University, Department of Physics, Georgetown University

  • Hartmut Hafermann

    Centre de Physique Theorique, Ecole Polytechnique, Centre de Physique Theorique, Ecole Polytechnique, CNRS, France

  • Ka-Ming Tam

    Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA, Louisiana State University (LSU), Louisiana State University, Department of Physics and Astronomy, Louisiana State University, Department of Physics \& Astronomy, Louisiana State University

  • Juana Moreno

    Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA, Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803, USA, Louisiana State University, Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA, Department of Physics and Astronomy, Louisiana State University, Department of Physics \& Astronomy, Louisiana State University

  • Thomas Pruschke

    Department of Physics, University of Goettingen, Germany

  • Mark Jarrell

    Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA, Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803, USA, Louisiana State University, Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA, Louisiana State University (LSU), Department of Physics and Astronomy, Louisiana State University, Department of Physics \& Astronomy, Louisiana State University