Polarization-Sensitive Self-Powered Type-II GeSe/MoS2 Van der Waals Heterojunction Photodetector.
Polarization-Sensitive Self-Powered Type-II GeSe/MoS2 Van der Waals Heterojunction Photodetector.
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DOI：
10.1021/acsami.0c01405
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发表时间：
2020-03
影响因子：
9.5
通讯作者：
Ye Xin;Xinxin Wang;Zhuo Chen;D. Weller;Yingying Wang;Li-jie Shi;Xiao Ma;Chunjie Ding;
中科院分区：
文献类型：
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作者：
Ye Xin;Xinxin Wang;Zhuo Chen;D. Weller;Yingying Wang;Li-jie Shi;Xiao Ma;Chunjie Ding;
偏振敏感光电探测器对于高性能光学信号捕获和杂散光屏蔽是非常需要的，以便增强在黑暗、雾霾和其他复杂环境中检测和识别目标的能力。通常，滤波器和偏振器用于常规装置以实现偏振敏感检测。本文中，为了简化光学系统，基于堆叠的GeSe/MoS 2货车德瓦耳斯（vdWs）异质结制造2-D自供电偏振敏感光电探测器，由于II型能带对准，该异质结有利于光生载流子的有效分离和传输。在此基础上，实现了高性能的自供电光电探测器，其零偏压下的开关比光电流为104，响应度（Rλ）为105 mA/W，外量子效率（EQE）为24.2%。此外，由于在宽光谱区域中的高吸收系数，宽光谱光响应从380 nm扩展到1064 nm。层状GeSe的这些高度各向异性正交结构的关键益处之一是峰/谷比高达2.95的自供电偏振敏感检测。这是实现用532 nm波长的激光照射，其中最大光响应度高达590 mA/W时，达到输入偏振平行于扶手椅方向。本工作为GeSe/MoS 2 vdW异质结自供电偏振敏感光电探测器的制备提供了一条简便的途径。
Polarization-sensitive photodetectors are highly desirable for high performance optical signal capture and stray light shielding in order to enhance the capability for detection and identification of targets in the dark, haze and other complex environments. Usually, filters and polarizers are utilized for conventional devices to achieve polarization-sensitive detection. Herein, to simplify the optical system, a 2-D self-powered polarization-sensitive photodetector is fabricated based on a stacked GeSe/MoS2 van der Waals (vdWs) heterojunction which facilitates efficient separation and transportation of the photogenerated carriers, due to type-II band alignment. Accordingly, a high performance self-powered photodetector is achieved with merits of a very large on-off ratio photocurrent at zero bias of currently 104 and a high responsivity (Rλ) of 105 mA/W with the external quantum efficiency (EQE) of 24.2%. Furthermore, a broad spectral photoresponse is extended from 380 nm to 1064 nm owing to the high absorption coefficient in a wide spectral region. One of the key benefits from these highly anisotropic orthorhombic structures of layered GeSe is self-powered polarization sensitive detection with a peak/valley ratio up to 2.95. This is realized irradiating with a 532 nm wavelength laser with which a maximum photoresponsivity of up to 590 mA/W is reached when the input polarization is parallel to the armchair direction. This work provides a facile route to fabricate self-powered polarization-sensitive photodetectors from GeSe/MoS2 vdW heterojunctions for integrated optoelectronic devices.