Finite-temperature charge dynamics and the melting of the Mott insulator

ORAL

Abstract

The Mott insulator is the quintessential strongly correlated electronic state. A full understanding of the coupled charge and spin dynamics of the Mott-insulating state is thought to be the key to a range of phenomena in ultracold atoms and condensed matter, including high-Tc superconductivity. Here we extend the slave-fermion (holon-doublon) description of the two-dimensional Mott insulator to finite temperatures. We benchmark its predictions against state-of-the-art quantum Monte Carlo simulations, finding quantitative agreement. Qualitatively, the short-ranged spin fluctuations at any finite temperatures are sufficient to induce holon-doublon bound states, and renormalize the charge sector to form the Hubbard bands. The Mott gap is understood as the charge (holon-doublon) gap renormalized downwards by these spin fluctuations. With increasing temperature, the Mott gap closes while the charge gap remains finite, causing a pseudogap regime to appear naturally during the process of melting the Mott insulator.

*This work was supported by the National Natural Science Foundation of China, by the National Basic Research Program of China and by the Chinese Academy of Sciences.

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Presenters

  • Bruce Normand

    • Paul Scherrer Institute, Switzerland
    • Paul Scherrer Institute
    • Neutrons and Muons Research Division, Paul Scherrer Institute
    • Paul Scherer Institute, Vilingen
    • Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland

Authors

  • Bruce Normand

    • Paul Scherrer Institute, Switzerland
    • Paul Scherrer Institute
    • Neutrons and Muons Research Division, Paul Scherrer Institute
    • Paul Scherer Institute, Vilingen
    • Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland

  • Xing-Jie Han

    • RWTH Aachen University, Aachen, Germany

  • Chuang Chen

    • Chinese Academy of Sciences (CAS), China
    • Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences
    • Institute of Physics, Chinese Academy of Science

  • Jing Chen

    • Chinese Academy of Sciences (CAS), China

  • Hai-Dong Xie

    • Chinese Academy of Sciences (CAS), China

  • Rui-Zhen Huang

    • Chinese Academy of Sciences (CAS), China

  • Hai-Jun Liao

    • Chinese Academy of Sciences (CAS), China
    • Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, China

  • Zi Yang Meng

    • Institute of Physics, Chinese Academy of Sciences
    • Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Science
    • Institute of physics, Chinese Academy of Sciences
    • Chinese Academy of Science
    • Chinese Academy of Sciences
    • Chinese Academy of Sciences (CAS), China
    • Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences
    • Institute of Physics, CAS
    • Institute of Physics, Chinese Academy of Science

  • Tao Xiang

    • Chinese Academy of Sciences (CAS), China
    • Institute of Physics
    • Institute of Physics, Chinese Academy of Sciences
    • Institute of Physics, CAS
    • Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, China