Multi-loop contributions in the pseudo-fermion functional renormalization group for quantum spin systems: implementation and consequences

ORAL

Abstract

We extend the pseudo-fermion functional renormalization group (PFFRG) treatment of quantum spin systems by including diagrammatic higher loop contributions into the renormalization group flow. This allows us to consistently account for all contributions of parquet-type diagrams in the two-particle vertex and self-energy derivatives within the two-particle truncated PFFRG flow. We will discuss the impact of these corrections in different quantum spin models within PFFRG, especially in the light of the Mermin-Wagner theorem.

*We acknowledge funding through ERC-StG-TOPOLECTRICS-336012 and DFG-SFB 1170 Project B04.

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Presenters

  • Tobias Müller

    • Institute for Theoretical Physics and Astrophysics, University of Wuerzburg
    • Institute for Theoretical Physics and Astrophysics, University of Würzburg

Authors

  • Tobias Müller

    • Institute for Theoretical Physics and Astrophysics, University of Wuerzburg
    • Institute for Theoretical Physics and Astrophysics, University of Würzburg

  • Yasir Iqbal

    • Indian Institute of Technology Madras
    • Department of Physics, Indian Institute of Technology Madras

  • Johannes Reuther

    • Dahlem Center for Complex Quantum Systems, Freie Universitat Berlin
    • Physics Department, Freie Universitaet Berlin
    • Physics, Freie Universität Berlin

  • Ronny Thomale

    • Institute for Theoretical Physics and Astrophysics, University of Wuerzburg
    • University of Wurzburg
    • Institute for theoretical physics, University of Wuerzburg
    • Institute for Theoretical Physics and Astrophysics, University Wuerzburg
    • Institut für Theoretische Physik und Astrophysik, Julius-Maximilians-Universität Würzburg
    • Univ of Wuerzburg
    • Institute for Theoretical Physics and Astrophysics, University of Würzburg
    • Institute for Theoretical Physics, University of Wuerzburg
    • Univ of Wurzburg