title: Tunable Polarity Behavior and Self-Driven Photoswitching in p-WSe₂/n-WS₂ Heterojunctions.
abstract: Van der Waals (vdW) p-n heterojunctions consisting of various 2D layer compounds are fascinating new artificial materials that can possess novel physics and functionalities enabling the next-generation of electronics and optoelectronics devices. Here, it is reported that the WSe2/WS2 p-n heterojunctions perform novel electrical transport properties such as distinct rectifying, ambipolar, and hysteresis characteristics. Intriguingly, the novel tunable polarity transition along a route of n-"anti-bipolar"-p-ambipolar is observed in the WSe2/WS2 heterojunctions owing to the successive work of conducting channels of junctions, p-WSe2 and n-WS2 on the electrical transport of the whole systems. The type-II band alignment obtained from first principle calculations and built-in potential in this vdW heterojunction can also facilitate the efficient electron-hole separation, thus enabling the significant photovoltaic effect and a much enhanced self-driven photoswitching response in this system.
authors: State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing, 100083, China.
authors: Nengjie
authors: N
authors: Huo
authors: State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing, 100083, China.
authors: Juehan
authors: J
authors: Yang
authors: State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing, 100083, China.
authors: Le
authors: L
authors: Huang
authors: State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing, 100083, China.
authors: Zhongming
authors: Z
authors: Wei
authors: State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing, 100083, China.
authors: Shu-Shen
authors: SS
authors: Li
authors: National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA.
authors: Su-Huai
authors: SH
authors: Wei
authors: State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing, 100083, China.
authors: Jingbo
authors: J
authors: Li
keywords: photoswitching, WSe2/WS2 heterojunctions; photovoltaics; self-driven photoswitching; tunable polarity