Metasurface-Based Photodetectors: Pursuing Superior Performance and Multifunctionality

Metasurfaces, composed of periodic subwavelength structures, provide a versatile platform for photodetector enhancement by enabling precise control over the amplitude, phase, polarization, and frequency. By tailoring the interaction between light and optoelectronic materials at the nanoscale, metasurfaces contribute to improved responsivity, faster response speed, and broader spectra. In addition, the compactness and integrability of metasurfaces make them well suited for the development of highly miniaturized and integrated photodetector architectures. This perspective begins with the fundamental principles of metasurface-based light modulation and relevant impact on photodetector performance. Recent advances in metasurface-based photodetectors are then discussed, highlighting an ultrafast response, enhanced sensitivity, broadband detection, and multifunctional capabilities, including polarization detection, spectral imaging, and multidimensional light field sensing. Challenges related to efficiency optimization, large-scale fabrication, and seamless integration with existing optoelectronic technologies are mentioned, with particular attention paid to cost-effectiveness and reproducibility. Finally, this review outlines prospective research directions, emphasizing the role of nanofabrication strategies, novel material platforms, and computational design methods in advancing metasurface-based photodetectors. The insights presented in this review are expected to serve as a reference for future studies and technological advancements in metasurface-based photodetectors.