Strongly Anisotropic Quasi‐1D BaTiS<sub>3</sub> Chalcogenide Perovskite for Near‐Infrared Polarized Photodetection
Feifan Yang, Kanghua Li, Mingzhi Fan, Wendian Yao, Liuchong Fu, Changying Xiong, Shenglin Jiang, Dehui Li, Ming Xu, Chao Chen, Guangzu Zhang, Jiang Tang
Abstract
Abstract One‐dimensional (1D) crystal‐structural materials have attracted extensive attention for polarization detection because of the strong anisotropy. Barium titanium sulfide (BaTiS 3 ), a quasi‐1D chalcogenide perovskite, demonstrates a great potential for polarization detection stemming from the giant optical anisotropy. Whereas, the photoelectric properties of BaTiS 3 and its direct application in polarized photodetector are less studied. Herein, quasi‐1D BaTiS 3 is introduced in polarized photodetection for the first time. The needle‐like BaTiS 3 single crystals are successfully prepared by a modified chemical vapor transport process. The BaTiS 3 single crystal demonstrates a narrow bandgap of 0.8 eV, an n‐type intrinsic conductivity, and a more than 300 cm 2 V −1 s −1 mobility along the c ‐axis. Then, an Ag/BaTiS 3 /Ag photoconductive detector is fabricated. It shows a broad detection wavelength ranging from visual light to 1550 nm and high responsivity of ≈1.22 A W −1 . Moreover, an orthogonal reverse property of polarization photocurrent is observed under the excitation energy of 1.70 eV and 1.96 eV. These comprehensive characteristics can promote the application of the quasi‐1D BaTiS 3 in near‐infrared polarized photodetection.