Li Ling, Gao Ge, Liu Xueting, Sun Yiming, Lei Jianpeng, Chen Zecheng, Dan Zhiying, Gao Wei, Zheng Tao, Wang Xiaozhou, Huo Nengjie, Li Jingbo
Institute of Semiconductors, South China Normal University, Guangzhou, 510631, P. R. China.
Nanchang Hangkong University, Nanchang, 330036, P. R. China.
Small. 2022 Aug;18(34):e2202523. doi: 10.1002/smll.202202523. Epub 2022 Jul 29.
Polarization-sensitive photodetectors based on van der Waals heterojunctions (vdWH) have excellent polarization-resolved optoelectronic properties that can enable the applications in polarized light identification and imaging. With the development of optical microcomputer control systems (OMCS), it is crucial and energy efficient to adopt the self-powered and polarization-resolved signal-generators to optimize the circuit design of OMCS. In this work, the selenium (Se) flakes with in-plane anisotropy and p-type character are grown and incorporated with n-type tungsten disulfide (WS ) to construct the type-II vdWH for polarization-sensitive and self-powered photodetectors. Under 405 nm monochrome laser with 1.33 mW cm power density, the photovoltaic device exhibits superior photodetection performance with the photoelectric conversion efficiency (PCE) of 3.6%, the responsivity (R) of 196 mA W and the external quantum efficiency (EQE) of about 60%. The strong in-plane anisotropy of Se crystal structure gives rise to the capability of polarized light detection with anisotropic photocurrent ratio of ≈2.2 under the 405 nm laser (13.71 mW cm ). Benefiting from the well polarization-sensitive and photovoltaic properties, the p-Se/n-WS vdWH is successfully applied in the OMCS as multivalued signal trigger. This work develops the new anisotropic vdWH and demonstrates its feasibility for applications in logic circuits and control systems.
基于范德华异质结（vdWH）的偏振敏感光电探测器具有出色的偏振分辨光电特性，可用于偏振光识别和成像。随着光学微计算机控制系统（OMCS）的发展，采用自供电且能分辨偏振的信号发生器来优化OMCS的电路设计至关重要且节能高效。在这项工作中，生长出具有面内各向异性和p型特性的硒（Se）薄片，并将其与n型二硫化钨（WS₂）结合，构建用于偏振敏感和自供电光电探测器的II型vdWH。在功率密度为1.33 mW/cm²的405 nm单色激光照射下，该光电器件展现出卓越的光电探测性能，光电转换效率（PCE）为3.6%，响应度（R）为196 mA/W，外部量子效率（EQE）约为60%。Se晶体结构强烈的面内各向异性使其具备偏振光探测能力，在405 nm激光（13.71 mW/cm²）照射下，各向异性光电流比约为2.2。得益于良好的偏振敏感和光伏特性，p-Se/n-WS₂ vdWH成功应用于OMCS作为多值信号触发器。这项工作开发了新型各向异性vdWH，并证明了其在逻辑电路和控制系统中应用的可行性。
