High-Performance Black Arsenic Photodetector Assisted by Multi-Mechanisms Effects Detecting From Visible to Terahertz

Defects such as high dark current, low temperature working conditions, low flexibility hinder the development of traditional material photodetectors. While some innovative low-dimensional materials, such as black phosphorus, are highly unstable. As a twin material of black phosphorus, black arsenic (b-As) has excellent properties of black phosphorus and relatively eliminates the characteristics of instability. Here, a high-performance photodetector based on black arsenic is proposed in detecting visible, near infrared and terahertz. The b-As photodetector exhibits a fast response speed while maintaining a responsivity of 647.5 V/W and a noise equivalent power of $2.30\times 10 ^{-11}$ W/Hz $^{1/2}$ under 520 nm irradiation. Assisted by photoconductive effect and thermal effect, we explain the reason for its detection of visible, near infrared and terahertz respectively. Moreover, this b-As photodetector exhibits high-resolution imaging capability on target band. By demonstrating the significant potential of b-As in the realm of broadband photodetection, our research presents a promising avenue for future optoelectronic applications.