Self-Driven Fast-Speed Photodetector Based on BP/ReS2 van der Waals Heterodiode

Broadband photodetectors based on 2D layered materials provide great potential applications in night vision, sensing, and communications. However, it remains a challenge for detectors to achieve both high photoresponsivity and fast response. Here, a high-sensitive photodetector based on ReS2/BP van der Waals (vdW) heterodiode with fast speed, rising time (tau(r)) of 770 ns, and decay time (tau(d)) of 760 ns under a 637 nm laser is reported. The detection range is covered from visible to mid-wave infrared (MWIR) 0.405-3.753 mu m. In the visible range, a high photoresponsivity of 107.1 AW(-1), competitive specific detectivity (D*) of 1.89 x 10(10) cm Hz(1/2) W-1, and a low noise equivalent power of 3.03 x 10(-14) W Hz(-1/2) are obtained. In the MWIR the D* of 3.26 x 10(8) cm Hz(1/2) W-1 is demonstrated in the photovoltaic model. Notably, the photodiode realizes a high external quantum efficiency of 71.8%, and a high power conversion efficiency of 2.0%. This work provides a way to design broadband response and fast-speed self-driven photodetectors with great potential applications in weak light intensity.