High Performance Self‐Driven Polarization‐Sensitive Photodetectors Based on GeAs/InSe Heterojunction. Issue 20 (16th July 2021)

• Record Type: Journal Article
• Authors: Xiong, Jingxian; Sun, Yiming; Wu, Liangwei; Wang, Weizhe; Gao, Wei; Huo, Nengjie; Li, Jingbo
• Is Part Of: Advanced optical materials. Volume 9:Issue 20(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-07-16
• Subjects: GeAs/InSe heterojunction -- polarization‐sensitive photodetectors -- self‐powered photodetectors -- type‐II band alignment; Optical materials -- Periodicals; Photonics -- Periodicals; 620.11295
• DOI: 10.1002/adom.202101017
• Languages: English
• ISSNs: 2195-1071

Abstract

Abstract: The ability to detect linearly polarized light is essential in the field of angle‐dependent optoelectronics and polarization optical applications. To date, most polarization‐sensitive photodetectors are mainly based on single 2D anisotropic materials, which still suffer from the large dark current, from being external bias driven, and from low anisotropy ratio. To address these obstacles, we fabricated a van der Waals (vdW) GeAs/InSe heterojunction with type‐II band alignment achieving a high‐performance self‐driven polarization‐sensitive photodetector. The heterojunction exhibits excellent rectifying characteristics with a current rectification ratio exceeding 10 3 . By operating in photovoltaic mode at zero bias, the device shows a very low dark current of ∼0.1 picoampere, high photoresponsivity of 357 mA/W, and large photo‐switching ratio of 10 3, yielding a high specific detectivity of 2 × 10 11 Jones and photoelectric conversion efficiency (PCE) up to 8%. Benefiting from the anisotropic structure of the GeAs components, the heterojunctions also exhibit self‐driven polarization‐sensitive photodetection with superior anisotropic photocurrent ratio of ∼18 which surpasses state‐of‐the‐art 2D based polarization‐dependent detectors. This work proposes an effective strategy utilizing the anisotropic/isotropic vdW heterojunctions to enable self‐powered and high‐performance polarization‐sensitive photodetectors, opening a new avenue towards the promising potential applications in polarization‐resolved electronics and photonics. Abstract : To achieve self‐driven polarization‐sensitive photodetectors, the anisotropic/isotropic GeAs/InSe heterojunction is designed and fabricated. Due to the type‐II band alignment and good p–n interface, the heterojunction exhibits excellent rectifying behavior and photovoltaic effect with power conversion efficiency up to 8%. Moreover, the device demonstrates superior polarization sensitivity with anisotropic photocurrent ratio of ≈18, surpassing state‐of‐the‐art 2D based polarization‐dependent detectors.