Bias-controlled vertical asymmetrical dual-Schottky junction photodetectors for direct linear polarimetry and AoLP imaging

Anisotropic two-dimensional (2D) materials have garnered significant attention in recent years due to their polarization-sensitive photoresponse. However, the inherent crystal structure fundamentally limits the polarization ratio of photocurrent to around 2, which is far below commercial requirements (> 10). Here, the polarimetric photodetector based on vertical asymmetrical 1T’ MoTe₂/MoS₂/1T’ MoTe₂ dual van der Waals (vdWs) Schottky junction was demonstrated. Owing to the unique vertical dual-Schottky junction, the device exhibits excellent performance under 915 nm illumination, including a fast rise/decay time of 40/36 μs, a broad 3 dB bandwidth of 12.5 kHz, and ultrahigh polarization ratios of 32 (0.045 V) and 47 (−0.015 V), potentially reaching infinity. Based on the outstanding response speed and polarization sensitivity, the device conveniently achieves polarization angle recognition for linear polarization light by switching external bias voltage without the aid of any polarizer or half-wave plate. In addition, the infrared angle of linear polarization (AoLP) imaging for a target obscured by a blocking film is demonstrated, in which targets with different polarization angles can be clearly distinguished. This work provides a novel scheme for next-generation integrated and all-in-one infrared polarimetric detection and imaging systems.