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arXiv · 1701.08619

Gate-Defined One-Dimensional Channel and Broken Symmetry States in MoS$_2$ van der Waals Heterostructures

Riccardo Pisoni·Yongjin Lee·Hiske Overweg·Marius Eich·Pauline Simonet·Kenji Watanabe·Takashi Taniguchi·Roman Gorbachev·Thomas Ihn·Klaus Ensslin
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Abstract

We have realized encapsulated trilayer MoS$_2$ devices with gated graphene contacts. In the bulk, we observe an electron mobility as high as 7000~cm$^{2}$/(V s) at a density of 3 $\times$ 10$^{12}$~cm$^{-2}$ at a temperature of 1.9~K. Shubnikov--de Haas oscillations start at magnetic fields as low as 0.9~T. The observed 3-fold Landau level degeneracy can be understood based on the valley Zeeman effect. Negatively biased split gate electrodes allow us to form a channel that can be completely pinched off for sufficiently large gate voltages. The measured conductance displays plateau-like features.

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Riccardo Pisoni, Yongjin Lee, Hiske Overweg, Marius Eich, Pauline Simonet, Kenji Watanabe, Takashi Taniguchi, Roman Gorbachev, Thomas Ihn, Klaus Ensslin. 2017-01-30. Gate-Defined One-Dimensional Channel and Broken Symmetry States in MoS$_2$ van der Waals Heterostructures. https://doi.org/10.1021/acs.nanolett.7b02186

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