Low-Noise Dual-Band Polarimetric Image Sensor Based on 1D Bi₂ S₃ Nanowire

With the increasing demand for detection accuracy and sensitivity, dual-band polarimetric image sensor has attracted considerable attention due to better object recognition by processing signals from diverse wavebands. However, the widespread use of polarimetric sensors is still limited by high noise, narrow photoresponse range, and low linearly dichroic ratio. Recently, the low-dimensional materials with intrinsic in-plane anisotropy structure exhibit the great potential to realize direct polarized photodetection. Here, strong anisotropy of 1D layered bismuth sulfide (Bi₂ S₃ ) is demonstrated experimentally and theoretically. The Bi₂ S₃ photodetector exhibits excellent device performance, which enables high photoresponsivity (32 A W^-1 ), I_on /I_off ratio (1.08 × 10⁴ ), robust linearly dichroic ratio (1.9), and Hooge parameter (2.0 × 10^-5 at 1 Hz) which refer to lower noise than most reported low-dimensional materials-based devices. Impressively, such Bi₂ S₃ nanowire exhibits a good broadband photoresponse, ranging from ultraviolet (360 nm) to short-wave infrared (1064 nm). Direct polarimetric imaging is implemented at the wavelengths of 532 and 808 nm. With these remarkable features, the 1D Bi₂ S₃ nanowires show great potential for direct dual-band polarimetric image sensors without using any external optical polarizer.