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arXiv · 1801.08932

Two-dimensional Mott variable-range hopping transport in a disordered MoS$_2$ nanoflake

Jianhong Xue·Shaoyun Huang·Ji-Yin Wang·H. Q. Xu
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Abstract

The transport characteristics of a disordered MoS$_2$ nanoflake in the insulator regime are studied by electrical and magnetotransport measurements. The layered MoS$_2$ nanoflake is exfoliated from a bulk MoS$_2$ crystal and the conductance $G$ and magnetoresistance are measured in a four-probe setup over a wide range of temperatures. At high temperatures, we observe that $\log_{10}G$ exhibits a $-T^{-1}$ temperature dependence and the transport in the nanoflake dominantly arises from thermal activation. At low temperatures, where the transport in the nanoflake dominantly takes place via variable-range hopping (VRH) processes, we observe that $\log_{10}G$ exhibits a $-T^{-1/3}$ temperature dependence, an evidence for the two-dimensional (2D) Mott VRH transport. The measured low-field magnetoresistance of the nanoflake in the insulator regime exhibits a quadratic magnetic field dependence $\sim \alpha B^2$ with $\alpha\sim T^{-1}$, fully consistent with the 2D Mott VRH transport in the nanoflake.

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Jianhong Xue, Shaoyun Huang, Ji-Yin Wang, H. Q. Xu. 2018-01-26. Two-dimensional Mott variable-range hopping transport in a disordered MoS$_2$ nanoflake. https://doi.org/10.1039/c9ra03150b

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