A self-powered photodetector based on a PdSe₂/WSe₂ Van der Waals heterojunction with broadband response and polarization sensitivity

Polarization-sensitive photodetectors based on two-dimensional (2D) anisotropic materials have exhibited promising potentials for applications in optical communication and optoelectronic fields. However, most of the reported polarization-sensitive photodetectors are limited by the challenges of high driving source-drain voltages and low photocurrent anisotropic ratios. Herein, we report a polarization-sensitive photodetector based on PdSe₂/WSe₂ van der Waals (vdW) heterostructure. The device achieves a self-powered broadband photoresponse from 520 nm to 1550 nm. The responsivity and specific detectivity reach up to 29 A/W and 4.05 × 10¹¹ Jones, respectively. Furthermore, the device is highly sensitive to polarized near-infrared light with a large dichroic ratio up to 2.79 under zero bias. Our work offers a promising route toward high-performance, low-power polarization-sensitive photodetection.