Xue Jianhong, Huang Shaoyun, Wang Ji-Yin, Xu H Q
Beijing Key Laboratory of Quantum Devices, Key Laboratory for the Physics and Chemistry of Nanodevices, Department of Electronics, Peking University Beijing 100871 China
Beijing Academy of Quantum Information Sciences West Bld. #3, No. 10 Xibeiwang East Rd., Haidian District Beijing 100193 China.
RSC Adv. 2019 Jun 6;9(31):17885-17890. doi: 10.1039/c9ra03150b. eCollection 2019 Jun 4.
The transport characteristics of a disordered, multilayered MoS nanoflake in the insulator regime are studied by electrical and magnetotransport measurements. The MoS nanoflake is exfoliated from a bulk MoS crystal and the conductance and magnetoresistance are measured in a four-probe setup over a wide range of temperatures. At high temperatures, we observe that ln exhibits a - 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 variable-range hopping (VRH) processes, we observe that ln exhibits a - temperature dependence, an evidence for the two-dimensional (2D) Mott VRH transport. Furthermore, we observe that the measured low-field magnetoresistance of the nanoflake in the insulator regime exhibits a quadratic magnetic field dependence ∼ with ∼ , fully consistent with the 2D Mott VRH transport in the nanoflake.
通过电学和磁输运测量研究了处于绝缘态的无序多层二硫化钼纳米片的输运特性。二硫化钼纳米片从块状二硫化钼晶体上剥离下来，并在四探针装置中在很宽的温度范围内测量其电导和磁电阻。在高温下，我们观察到ln 呈现出 - 温度依赖性，并且纳米片中的输运主要源于热激活。在低温下，纳米片中的输运主要通过变程跳跃（VRH）过程发生，我们观察到ln 呈现出 - 温度依赖性，这是二维（2D）莫特VRH输运的一个证据。此外，我们观察到处于绝缘态的纳米片的低场磁电阻呈现出二次磁场依赖性 ∼ ，其中 ∼ ，这与纳米片中的二维莫特VRH输运完全一致。
