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Tunable heavy fermions in a moiré Kondo lattice

ORAL

Abstract

The formation of heavy electrons by merging a lattice of local magnetic moments to a sea of itinerant electrons is a profound problem in condensed matter physics. The emergence of moiré materials provides a new platform to explore this problem in simple and tunable fashions. Here we report the realization of a tunable Kondo lattice in AB-stacked MoTe2/WSe2 moiré bilayers. Heavy electrons are formed when the MoTe2 layer is tuned to a strongly correlated Mott insulator, which supports a triangular lattice of local magnetic moments, and the WSe2 layer is doped with itinerant carriers. Over ten-fold enhancement in the electron mass is observed when the itinerant carriers and local moments form Kondo singlets. The Kondo singlets can be destroyed by an external magnetic field; a sharpened destruction at low temperatures suggests the presence of quantum criticality. Our study lays the foundation for exploring the Doniach phase diagram in semiconductor moiré materials.

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Presenters

  • Wenjin Zhao

    Cornell University, Kavli Institute at Cornell

Authors

  • Wenjin Zhao

    Cornell University, Kavli Institute at Cornell

  • Bowen Shen

    Cornell University

  • Zui Tao

    Cornell University

  • Zhongdong Han

    Cornell University

  • Kaifei Kang

    Cornell University

  • Kenji Watanabe

    National Institute for Materials Science, Research Center for Functional Materials, National Institute of Materials Science, Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-044, Japan, NIMS, Research Center for Functional Materials, National Institute for Materials Science, National Institute for Materials Science, Japan, Research Center for Functional Materials, National Institute for Materials Science, Tsukuba, Japan, NIMS Japan

  • Takashi Taniguchi

    National Institute for Materials Science, Kyoto Univ, International Center for Materials Nanoarchitectonics, National Institute of Materials Science, Kyoto University, International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-044, Japan, International Center for Materials Nanoarchitectonics, National Institute for Materials Science, National Institute for Materials Science, Japan, National Institute For Materials Science, NIMS, National Institute for Material Science, International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba, Japan, NIMS Japan

  • Kin Fai Mak

    Cornell University

  • Jie Shan

    Cornell University