Gate Dependent Photoluminescence in Two-dimensional Transition Metal Dichalcogenides van der Waals Heterostructure devices.

ORAL

Abstract

Single layer transition metal dichalcogenides (TMDC) are 2-dimensional (2D) semiconductors characterized by a direct optical bandgap in the order of 2 eV and large exciton binding energies (\textgreater 100 meV). We fabricate van der Waals heterostructure devices made of 2D TMDCs with hexagonal Boron nitride (h-BN) as gate dielectric, with top and bottom gate electrodes and ohmic contacts down to cryogenic temperatures (T $=$ 3K). We study the evolution of photoluminescence (PL) with electric field, carrier density, and temperature. Our measured low-temperature PL peaks show full width at half maxima on the order of \textasciitilde 1meV. The amplitude of the photoluminescence peak, corresponding to the neutral and charged exciton emission (also their energy), can be manipulated with top and bottom gates.

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Authors

  • Luis Juaregui

    • Harvard University
    • Harvard University, Physics Department
    • Harvard University, Department of Physics

  • Andrew Joe

    • Harvard University
    • Harvard University, Physics Department
    • Harvard University, Department of Physics

  • Kateryna Pistunova

    • Harvard University, Physics Department

  • Alex High

    • Harvard University, Physics Department

  • Kristiaan De Greve

    • Harvard University, Physics Department

  • Giovanni Scuri

    • Harvard University, Physics Department

  • You Zhou

    • Harvard University, Chemistry Department

  • Hongkun Park

    • Harvard University, Chemistry and Physics Department

  • Mikhail Lukin

    • Harvard University, Physics Department

  • Philip Kim

    • Harvard University, Physics Department