Self-Powered In2Se3/Ge Photodetector from Visible to Short-Wave Infrared Region

• Published in: Optics letters 2025-01, Vol.50 (1), p.29
• Main Authors: Li, Kuangkuang, Li, Wenbo, kang, ling, Liu, Xingzhao
• Format: Article
• Language: English
• ISSN: 0146-9592; 1539-4794; 1539-4794
• DOI: 10.1364/OL.542651

An In2Se3/Ge heterojunction is fabricated via molecular beam epitaxy. The p-n junction device features a broadened photosensitive spectrum ranging from a visible (VIS) to short-wave infrared (SWIR) region (400-1700 nm). Notably, self-powered high responsivity of 0.32 A/W@450 nm and 0.52 A/W@1550 nm, decent specific detectivity of 3.2 × 1011 Jones@450 nm, and 5.2 × 1011 Jones@1550 nm at zero bias are achieved. Moreover, our photodetector exhibits a fast response speed with a sub-millisecond response time. These results can be attributed to the high quality of the In2Se3-Ge interface. Benefiting from the superposable dual-band photoresponse, the potential of the device for encrypted optical communication has been demonstrated.An In2Se3/Ge heterojunction is fabricated via molecular beam epitaxy. The p-n junction device features a broadened photosensitive spectrum ranging from a visible (VIS) to short-wave infrared (SWIR) region (400-1700 nm). Notably, self-powered high responsivity of 0.32 A/W@450 nm and 0.52 A/W@1550 nm, decent specific detectivity of 3.2 × 1011 Jones@450 nm, and 5.2 × 1011 Jones@1550 nm at zero bias are achieved. Moreover, our photodetector exhibits a fast response speed with a sub-millisecond response time. These results can be attributed to the high quality of the In2Se3-Ge interface. Benefiting from the superposable dual-band photoresponse, the potential of the device for encrypted optical communication has been demonstrated.