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arXiv · 2102.03756

Room-temperature bipolar valleytronic transistor in MoS2/WSe2 heterostructures

Chongyun Jiang·Abdullah Rasmita·Hui Ma·Qinghai Tan·Zumeng Huang·Shen Lai·Sheng Liu·Xue Liu·Qihua Xiong·Wei-bo Gao
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Abstract

Valley degree of freedom in the 2D semiconductor is a promising platform for the next generation optoelectronics. Electrons in different valleys can have opposite Berry curvature, leading to the valley Hall effect (VHE). However, VHE without the plasmonic structure's assistance has only been reported in cryogenic temperature, limiting its practical application. Here, we report the observation of VHE at room temperature in the MoS2/WSe2 heterostructures. We also uncover that both the magnitude and the polarity of the VHE in the 2D heterostructure is gate tunable. We attribute this to the opposite VHE contribution from the electron and hole in different layers. These results indicate the bipolar transport nature of our valleytronic transistor. Utilizing this gate tunability, we demonstrate a bipolar valleytronic transistor. Our results can be used to improve the ON/OFF ratio of the valleytronic transistor and to realize more versatile valleytronics logic circuits.

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cond-mat.mes-hallcond-mat.mtrl-sciphysics.opticsquant-ph

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Chongyun Jiang, Abdullah Rasmita, Hui Ma, Qinghai Tan, Zumeng Huang, Shen Lai, Sheng Liu, Xue Liu, Qihua Xiong, Wei-bo Gao. 2021-02-07. Room-temperature bipolar valleytronic transistor in MoS2/WSe2 heterostructures. https://doi.org/10.1038/s41928-021-00686-7

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