Polarization-Sensitive Detector Based on MoTe₂/WTe₂ Heterojunction for Broadband Optoelectronic Imaging

Polarization-sensitive detectors have significant applications in modern communication and information processing. In this study. We present a polarization-sensitive detector based on a MoTe₂/WTe₂ heterojunction, where WTe₂ forms a favorable bandgap structure with MoTe₂ after forming the heterojunction. This enhances the carrier separation efficiency and photoelectric response. We successfully achieved wide spectral detection ranging from visible to near-infrared light. Specifically, under zero bias, our photodetector exhibits a responsivity (R) of 0.6 A/W and a detectivity (D*) of 3.6 × 10¹³ Jones for 635 nm laser illumination. Moreover, the photoswitching ratio can approach approximately 6.3 × 10⁵. Importantly, the polarization sensitivity can reach 3.5 (5.2) at 635 (1310) nm polarized light at zero bias. This study both unveils potential for utilizing MoTe₂/WTe₂ heterojunctions as polarization-sensitive detectors and provides novel insights for developing high-performance optoelectronic devices.