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arXiv · 1906.10389

Tunneling spectroscopy of localized states of $\mathrm{WS}_2$ barriers in vertical van der Waals heterostructures

Nikos Papadopoulos·Pascal Gehring·Kenji Watanabe·Takashi Taniguchi·Herre S. J. van der Zant·Gary A. Steele
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Abstract

In transition metal dichalcogenides, defects have been found to play an important role, affecting doping, spin-valley relaxation dynamics, and assisting in proximity effects of spin-orbit coupling. Here, we study localized states in $\mathrm{WS}_2$ and how they affect tunneling through van der Waals heterostructures of h-BN/graphene/$\mathrm{WS}_2$/metal. The obtained conductance maps as a function of bias and gate voltage reveal single-electron transistor behavior (Coulomb blockade) with a rich set of transport features including excited states and negative differential resistance regimes. Applying a perpendicular magnetic field, we observe a shift in the energies of the quantum levels and information about the orbital magnetic moment of the localized states is extracted.

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Nikos Papadopoulos, Pascal Gehring, Kenji Watanabe, Takashi Taniguchi, Herre S. J. van der Zant, Gary A. Steele. 2019-06-25. Tunneling spectroscopy of localized states of $\mathrm{WS}_2$ barriers in vertical van der Waals heterostructures. https://doi.org/10.1103/physrevb.101.165303

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