Microscopic insights to ARPES spectra of doped quantum anti-ferromagnets

ORAL

Abstract

The phase diagram of cuprates, often modeled by the 2D Fermi Hubbard or $t-J$ model, remains poorly understood at low doping. Here we present new theoretical insights to the ARPES spectrum of quantum anti-ferromagnets at low doping: We argue that, at strong coupling $t \gg J$, the spectrum directly reflects the spectral function of a spinon which forms a universal bound state with the chargon created in the measurement. Our result is relevant to cuprates in the pseudogap regime: we interpret the the observed Fermi-arcs in a fractionalized Fermi liquid (FL*) picture and argue that the strongly suppressed spectral weight on the back-side of the hole pocket is a signature for the Dirac-fermion nature of the underlying spinons. We present DMRG calculations of the one-hole spectrum, which support the existence of the universal spinon-chargon bound state we assume at strong couplings. Our results are also relevant for the search of Dirac spinons in a larger class of frustrated quantum magnets.

Presenters

  • Fabian Grusdt

    • Department of Physics and Arnold Sommerfeld Center for Theoretical Physics (ASC), Ludwig-Maximilians-Universit\"at M\"unchen, Theresienstr. 37, M\"unchen D-80333, Germany

Authors

  • Fabian Grusdt

    • Department of Physics and Arnold Sommerfeld Center for Theoretical Physics (ASC), Ludwig-Maximilians-Universit\"at M\"unchen, Theresienstr. 37, M\"unchen D-80333, Germany
  • Annabelle Bohrdt

    • Tech Univ Muenchen
    • Department of Physics and Institute for Advanced Study, Technical University of Munich, 85748 Garching, Germany
  • Frank Pollmann

    • Physics, Technische Universitat Munchen
    • TU Munich
    • Technical University of Munich
    • Department of Physics, Technical University of Munich
    • Tech Univ Muenchen
    • Department of Physics, T42, Technical University of Munich, D-85748 Garching, Germany
  • Michael Knap

    • TU Munich
    • Department of Physics, Technical University of Munich
    • Technical University of Munich
    • Tech Univ Muenchen
    • Department of Physics and Institute for Advanced Study, Technical University of Munich, 85748 Garching, Germany