Direct Polarimetric Image Sensor and Wide Spectral Response Based on Quasi‐1D Sb<sub>2</sub>S<sub>3</sub> Nanowire
Kai Zhao, Juehan Yang, Mianzeng Zhong, Qiang Gao, Yang Wang, Xiaoting Wang, Wanfu Shen, Chunguang Hu, Kaiyou Wang, Guozhen Shen, Ming Li, Jianlu Wang, Weida Hu, Zhongming Wei
Abstract
Abstract Polarized photodetectors with wide spectral detection and ultra‐fast photoresponses based on anisotropic semiconductors have potential applications in military and civilian fields and have been widely studied in recent years. The dual advantages of low‐symmetry crystal structure and special electronic band‐structure make Sb 2 S 3 the perfect choice for polarized photodetection. In this work, the optical, vibrational, and optoelectronic anisotropy of the high‐quality orthorhombic Sb 2 S 3 nanowires are systematically investigated by experimental and theoretical studies. The metal‐semiconductor‐metal photodetectors based on a single Sb 2 S 3 nanowire exhibit good polarization sensitivity in a broadband range from ultraviolet to near‐infrared (360 to 1550 nm) and the obtained maximum dichroic ratio is 2.54 at 638 nm. The polarization‐sensitive photocurrent mapping results show that the photocurrent is mainly derived from the Schottky junction at the interface between Au and Sb 2 S 3 . The effective separation of the photo‐generated carriers near the Schottky junction gives a photodetector response time of 470 µs. The direct polarimetric imaging demonstrates that the gray value of the image obtained by the imaging system is sensitive to the object's polarized direction. This natural sensitivity of the Sb 2 S 3 ‐based photodetector to polarized objects makes it possible to image polarized objects directly as an image sensor.