Quantum Spin Liquids Unveil the Genuine Mott State

ORAL

Abstract

The Widom line identifies the supercritical crossover from a gas-like to a more liquid-like behavior. A similar transition exists in correlated electron liquids, where the interplay of Coulomb repulsion, bandwidth and temperature triggers between the Mott insulating state and an incoherent conduction regime. Here we explore the electrodynamic response of three organic quantum spin liquids, where the absence of magnetic order enables unique insight into the nature of the genuine Mott state. Combining optical spectroscopy with pressure-dependent dc transport and theoretical calculations, we succeeded to construct a phase diagram valid for all Mott insulators on a quantitative scale. Our findings reveal the Pomeranchuk-like anomaly of the Mott transition and metallic fluctuations within the Mott gap, previously predicted but never observed.

*Part of the work is supported by the Deutsche Forschungsgemeinschaft (DFG) via DR228/41-1, DR228/48-1, and the Deutscher Akademischer Austauschdienst (DAAD). We acknowledge the JSPS KAKENHI Grant Number JP16H06346 and the Russian Ministry of Education and Science (Program “5 top 100”). We also acknowledg

Presenters

  • Andrej Pustogow

    • University of Stuttgart

Authors

  • Andrej Pustogow

    • University of Stuttgart
  • Mathias Bories

    • University of Stuttgart
  • Anja Löhle

    • University of Stuttgart
  • Roland Rösslhuber

    • University of Stuttgart
  • Elena Zhukova

    • Moscow Institute of Physics and Technology
  • Boris Gorshunov

    • Moscow Institute of Physics and Technology
  • Silvia Tomic

    • Institut za fiziku
  • John Schlueter

    • Division of Materials Research, National Science Foundation
    • Materials Science Division, Argonne National Laboratory, Argonne
  • Ralph Hübner

    • University of Stuttgart
  • Takaaki Hiramatsu

    • Meijo University
  • Yukihiro Yoshida

    • Meijo University
  • Gunzi Saito

    • Meijo University
    • Meijo Univ
  • Reizo Kato

    • RIKEN
    • Condensed Molecular Materials Labolatory, RIKEN
  • Tsung-Han Lee

    • Florida State University
  • Vladimir Dobrosavljevic

    • Florida State University
  • Simone Fratini

    • Institut Neel, Universite Grenoble Alpes
  • Martin Dressel

    • University of Stuttgart