Synergistic Anisotropy Engineering in Ta ₂ NiSe ₅ /Violet Phosphorus Heterostructures for High‐Performance Polarization‐Sensitive Photodetection

Polarization‐sensitive photodetection, which extracts the vector information of light, is indispensable for emerging technologies ranging from encrypted optical communications and space navigation to biomedical imaging. Achieving high‐sensitivity broadband photodetection with intrinsic polarization selectivity remains a critical challenge in post‐Moore optoelectronics, largely restricted by the intrinsic trade‐offs in quantum efficiency and dichroism of single‐component materials. Here, we demonstrate a high‐performance polarization‐sensitive photodetector based on a two‐dimensional van der Waals heterojunction composed of tantalum nickel selenide and violet phosphorus. Benefiting from the synergistic anisotropy and efficient interfacial charge transport, the device exhibits exceptional optoelectronic performance across a broad spectral range (520–1550 nm). Specifically, the device achieves a high responsivity ( R ) of 101 mA/W, specific detectivity ( D * ) of 1.73 × 10 11 Jones, and a low noise‐equivalent power (NEP) of 5.16 × 10 −15 W Hz −1/2 . The heterojunction maintains robust polarization sensitivity, delivering a dichroic ratio of 4.09 in the visible region and 3.35 at 940 nm. Furthermore, we demonstrate the practical viability of the device through high‐contrast polarization imaging, revealing its potential for encrypted communication and navigation.