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arXiv · 2404.02427

In-situ tunable giant electrical anisotropy in a grating gated AlGaN/GaN two-dimensional electron gas

Ting-Ting Wang·Sining Dong·Chong Li·Wen-Cheng Yue·Yang-Yang Lyu·Chen-Guang Wang·Chang-Kun Zeng·Zixiong Yuan·Wei Zhu·Zhi-Li Xiao·Xiaoli Lu·Bin Liu·Hai Lu·Hua-Bing Wang·Peiheng Wu·Wai-Kwong Kwok·Yong-Lei Wang
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Abstract

Materials with in-plane electrical anisotropy have great potential for designing artificial synaptic devices. However, natural materials with strong intrinsic in-plane electrical anisotropy are rare. We introduce a simple strategy to produce extremely large electrical anisotropy via grating gating of a semiconductor two-dimensional electron gas (2DEG) of AlGaN/GaN. We show that periodically modulated electric potential in the 2DEG induces in-plane electrical anisotropy, which is significantly enhanced in a magnetic field, leading to an ultra large electrical anisotropy. This is induced by a giant positive magnetoresistance and a giant negative magnetoresistance under two orthogonally oriented in-plane current flows, respectively. This giant electrical anisotropy is in-situ tunable by tailoring both the grating gate voltage and the magnetic field. Our semiconductor device with controllable giant electrical anisotropy will stimulate new device applications, such as multi-terminal memtransistors and bionic synapses.

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Ting-Ting Wang, Sining Dong, Chong Li, Wen-Cheng Yue, Yang-Yang Lyu, Chen-Guang Wang, Chang-Kun Zeng, Zixiong Yuan, Wei Zhu, Zhi-Li Xiao, Xiaoli Lu, Bin Liu, Hai Lu, Hua-Bing Wang, Peiheng Wu, Wai-Kwong Kwok, Yong-Lei Wang. 2024-04-03. In-situ tunable giant electrical anisotropy in a grating gated AlGaN/GaN two-dimensional electron gas. https://doi.org/10.1063/5.0097518

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