Polarized Photodetectors Based on 2D 2H‐MoTe2/1T'‐MoTe2/MoSe2 Van Der Waals Heterojunction

Abstract

AbstractThe van der Waals heterojunction based on transition metal dichalcogenides has broad research value and application prospects as the basic material for advanced near‐infrared polarized photodetectors. a type II heterojunction based on the 2H‐MoTe2/1T′‐MoTe2/MoSe2 structure is reported for photovoltaic photodetectors. Notably, this device generates a self‐powered photocurrent, eliminating the need for an external bias or gate voltage. This device has the ability to detect polarized light, and its photocurrent anisotropy ratio is 55. The device performance is significantly amplified due to the proficient facilitation of electron‐hole separation through the type II band structure of MoSe2 at the bottom and 2H‐MoTe2 at the top, as well as enhanced exciton splitting by 1T′‐MoTe2 situated in the middle. Consequently, the device demonstrates exceptional proficiency, presenting a noteworthy response rate of 0.76 A W−1, a high detection rate of 3 × 109 Jones, an elevated EQE of 71%, and rapid rising and falling response speeds of 13 ms/10 ms respectively. Moreover, the device's anisotropy ratio of photocurrent highlights its sensitivity to polarized light, making it a promising candidate for applications in polarized photodetection. Overall, this innovative heterostructure opens new avenues for exploring and developing advanced optoelectronic devices based on 2D van der Waals materials.