Thermal and Quantum Melting Phase Diagrams for a Magnetic-Field-Induced Wigner Solid

ORAL

Abstract

In a strongly interacting two-dimensional (2D) electron system, when the Coulomb energy dominates over the kinetic energy, the electrons tend to arrange periodically and form a so-called Wigner solid (WS) ground state. In a GaAs 2D electron system, a magnetic-field-induced quantum WS forms at very low temperature and high magnetic field near filling factor v = 1/5 when the kinetic (Fermi) energy is quenched and the Coulomb energy dominates. In a dilute GaAs 2D hole system, on the other hand, the WS phase forms near v = 1/3 because of the significant Landau level mixing caused by the large hole effective mass. Here we report our measurements [1], using a newly developed technique which probes the melting of the WS via its screening efficiency, of the fundamental temperature vs. filling phase diagram for the 2D holes' WS-liquid thermal melting. Moreover, via changing the 2D holes' density, we also probe their Landau level mixing vs. filling WS-liquid quantum melting phase diagram. We find our data to be in good agreement with the results of very recent calculations [2].

[1] M. K. Ma et al., PRL 125, 036601 (2020).
[2] J. Zhao et al., PRL 121, 116802 (2018).

*DOE BES (DE-FG02-00-ER45841), NSF (DMR 1709076, ECCS 1906253, MRSEC DMR 1420541), Gordon and Betty Moore Foundation (GBMF9615).

Presenters

  • K. A. Villegas-Rosales

    • Princeton University

Authors

  • Meng Ma

    • Princeton University
  • K. A. Villegas-Rosales

    • Princeton University
  • Hao Deng

    • Princeton University
  • Edwin Yoonjang Chung

    • Princeton University
  • Loren Pfeiffer

    • Princeton University
    • Princeton Institute for the Science and Technology of Materials (PRISM), Princeton University
    • Department of Electrical Engineering, Princeton University
    • Electrical Engineering, Princeton
    • Electrical Engineering, Princeton University
    • Princeton
  • Ken W. West

    • Princeton University
    • Princeton Institute for the Science and Technology of Materials (PRISM), Princeton University
    • Department of Electrical Engineering, Princeton University
    • Electrical Engineering, Princeton
    • Electrical Engineering, Princeton University
    • Princeton
  • Kirk Baldwin

    • Princeton Institute for the Science and Technology of Materials (PRISM), Princeton University
    • Princeton University
    • Department of Electrical Engineering, Princeton University
    • Electrical Engineering, Princeton
    • Electrical Engineering, Princeton University
  • Roland Winkler

    • Northern Illinois University
  • Mansour Shayegan

    • Department of Electrical Engineering, Princeton University
    • Princeton University