Imaging Wigner crystal (part I)

ORAL

Abstract

Electron crystalizes when Coulomb interaction is largely greater than kinetic energy. In two dimensions, the kinetic energy of the electrons can be further quenched by applying a perpendicular magnetic field. The so-called magnetic field induced Wigner Crystal (WC) forms at low Landau level filling factor and has been extensively studied during the past 40 years. However, direct visualization of its lattice structure and symmetry has never been confirmed. Here, we perform high resolution scanning tunneling microscopy (STM) at mK temperature in Bernal-stacked bilayer graphene. We reveal the crystal symmetry of the WC and identify the relationship between the lattice constant and the filling factor of the crystal. Our study provides unambiguous evidence of the WC and paves the way for imaging exotic phases such as, skyrme crystal, quasi-particle WC, stripe phases, and bubble phases, etc.





* Funding Acknowledgement: DOE, Moore Foundation, NSF-DMR, NSF-MRSEC, and ONR

* DOE, Moore Foundation, NSF-DMR, NSF-MRSEC, and ONR

–

Presenters

  • Yen-Chen Tsui

    Princeton University

Authors

  • Yen-Chen Tsui

    Princeton University

  • Minhao He

    Princeton University

  • Yuwen Hu

    Princeton University

  • Taige Wang

    University of California, Berkeley

  • Ethan A Lake

    University of California, Berkeley

  • Kenji Watanabe

    National Institute for Materials Science, NIMS, Research Center for Electronic and Optical Materials, National Institute for Materials Science, Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, National Institute for Material Science

  • Takashi Taniguchi

    Kyoto Univ, National Institute for Materials Science, Research Center for Materials Nanoarchitectonics, Research Center for Materials Nanoarchitectonics, National Institute for Materials Science, National Institute for Materials Sciences, NIMS, International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, National Institute for Material Science, International Center for Materials Nanoarchitectonics, NIMS, Japan, International Center for Materials Nanoarchitectonics, Tsukuba, National Institue for Materials Science, Kyoto University, National Institute of Materials Science, International Center for Materials Nanoarchitectonics and National Institute for Materials Science

  • Michael P Zaletel

    University of California, Berkeley, University of Berkerley, UC Berkeley

  • Ali Yazdani

    Princeton University