Spin-Enhanced Self-Powered Light Helicity Detecting Based on Vertical WSe 2 -CrI 3 p-n Heterojunction

• Published in: ACS nano 2024-09
• Main Authors: Chen, Jiamin, Cheng, Zhixuan, Chen, Jiahao, Li, Minglai, Jia, Xionghui, Ran, Yuqia, Zhang, Yi, Li, Yanping, Yu, Tongjun, Dai, Lun
• Format: Article
• Language: English
• ISSN: 1936-0851; 1936-086X
• DOI: 10.1021/acsnano.4c08185

Two-dimensional (2D) magnetic semiconductors offer an intriguing platform for investigating magneto-optoelectronic properties and hold immense potential in developing prospective devices when they are combined with valley electronic materials like 2D transition-metal dichalcogenides. Herein, we report various magneto-optoelectronic response features of the vertical hBN-FLG-CrI -WSe -FLG-hBN van der Waals heterostructure. Through a sensible layout and exquisite manipulation, an hBN-FLG-CrI -FLG-hBN heterostructure was also fabricated on identical CrI and FLGs for better comparison. Our results show that the WSe -CrI heterostructure, acting as a - heterojunction, has advantageous capability in light detection, especially in self-powered light helicity detecting. In the WSe -CrI heterojunction, the absolute value of photocurrent exhibits obvious asymmetry with respect to the bias , with the of reversely biased WSe -CrI heterojunction being larger. When the CrI is fully spin-polarized under a 3 T magnetic field, the reversely biased WSe -CrI heterojunction exhibits advantageous capability in light helicity detecting. Both the short-circuit currents and show one-cycle fluctuation behaviors when the quarter-wave plate rotates 180°, and the corresponding photoresponsivity helicities can be as high as 18.0% and 20.1%, respectively. We attribute the spin-enhanced photovoltaic effect in the WSe -CrI heterojunction and its contribution to circularly polarized light detection to the coordination function of the spin-filter CrI , the valley electronic monolayer WSe , and the spin-dependent charge transfer between them. Our work helps us understand the interplay between the magnetic and optoelectronic properties of WSe -CrI heterojunctions and promotes the developing progress of prospective 2D spin optoelectronic devices.