Research progress of polarization performance of plasmon-enhanced van der Waals photodetectors

Polarization detection is a fundamental way to obtain the vectorial nature of light, supporting advanced technologies in the fields of optical communication, intelligent sensing, and biosensing. Two-dimensional van der Waals materials have become a promising platform for high-performance polarization-sensitive photodetectors due to their inherent anisotropy and tunable electronic properties. Nevertheless, their intrinsically weak light absorption and limited photoresponse efficiency remain major bottlenecks. Plasmonic nanostructures, which can achieve strong localized field confinement and manipulation on a nanoscale, provide an effective strategy to overcome these limitations and substantially improve device performance. In this review, we systematically summarize the coupling mechanisms between plasmonic architectures and vdW materials, highlighting near-field enhancement, plasmon-induced hot-carrier generation, and mode-selective polarization coupling as key physical processes for enhancing photocarrier generation and polarization extinction. Representative devices including metallic gratings, hybrid nanoantennas, and chiral metasurfaces are compared in terms of responsivity, detection speed, operating bandwidth, and polarization extinction ratio, revealing consistent improvements of one to two orders of magnitude over bare vdW devices. We further survey emerging applications in the fields of high-speed polarization-encoded optical communication, on-chip optical computing and information processing, and bioinspired vision and image recognition systems, where plasmonic-vdW hybrid detectors demonstrate unique advantages in miniaturization and energy efficiency. Finally, we discuss current challenges such as large-scale fabrication of uniform plasmonic arrays, spectral bandwidth broadening, and seamless integration with complementary photonic circuits, and outline future opportunities for next-generation polarization-resolved optoelectronic platforms.