Photocurrent measurements in Coupled Quantum Well van der Waals Heterostructures made of 2D Transition Metal Dichalcogenides.

ORAL

Abstract

, Luis A. Jauregui, Alex A. High, Alan Dibos, Elgin Gulpinar, Kateryna Pistunova, Hongkun Park, Philip Kim Harvard University, Physics Department -abstract- Single layer transition metal dichalcogenides (TMDC) are 2-dimensional (2D) semiconductors van der Waals (vdW) characterized by a direct optical bandgap in the visible wavelength (\textasciitilde 2 eV). Characterization of the band alignment between TMDC and the barrier is important for the fabrication of tunneling devices. Here, we fabricate coupled quantum well (CQW) heterostructures made of 2D TMDCs with hexagonal Boron nitride (hBN) as an atomically thin barrier and gate dielectric and with top and bottom metal (or graphite) as gate electrodes. We observe a clear dependence of the photo-generated current with varying hBN thickness, electrode workfunctions, electric field, laser excitation power, excitation wavelength, and temperature. We will discuss the implication of photocurrent in relation to quantum transport process across the vdW interfaces.

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Authors

  • Andrew Joe

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

  • Luis Jauregui

    Harvard University, Physics Department

  • Alex High

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

  • Alan Dibos

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

  • Elgin Gulpinar

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

  • Kateryna Pistunova

    Harvard University, Physics Department

  • Hongkun Park

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

  • Philip Kim

    Harvard University, Department of Physics, Department of Physics, Harvard University, Cambridge, MA 02138, USA, Harvard University, Physics Department, Harvard University