Plasmonic structures have been widely employed to manipulate the light coupling of infrared detectors to enhance sensitivity and achieve multidimensional light field recognition. Recently, cavity coupled plasmonic resonators as an improved version of plasmonic light coupling structures have received much attention. A variety of ordinary plasmonic structure integrated infrared detectors and cavity coupled plasmonic resonator integrated infrared detectors are reviewed. Compared with ordinary plasmonic structures, cavity coupled plasmonic resonators are more effective in adjusting the light in-coupling efficiency, local field polarization, and light absorption competition, which is beneficial to performance enhancement in infrared detectors. Several features of cavity coupled plasmonic resonator integrated infrared detectors, including deep subwavelength light concentration with high efficiency, Ohmic loss suppression, high-contrast polarization discrimination, are discussed. As a brief outlook, cavity coupled plasmonic resonators for infrared detectors are expected to have optical-electrical joint functions, be compatible with focal plane array technology, and have new features stemming from innovative combinations of different kinds of cavities and plasmonic structures.

The application fields of infrared photodetectors are quite extensive. Compared with traditional infrared photodetection materials such as IV and III–V semiconductors, newly emerging low‐dimensional materials and quantum materials (e.g., 2D materials and quantum wells) have many advantages in different aspects, such as wide spectral range, low dark current, room temperature operation, and high processing compatibility. However, the performance of photodetectors based on low‐dimensional materials is limited by the ultra small thicknesses, polarization selectivity, and the poor absorption efficiency. Therefore, improving the performance of infrared photodetectors based on low‐dimensional materials has been a focus research task in recent years. The integration of photonic structures can improve the performance of infrared photodetectors, such as enhancing absorption efficiency, reducing the volume of active materials, and increasing polarization selectivity. Herein, different kinds of photonic structure integrated infrared photodetectors, roughly divided into two categories, namely, dielectric photonic structure integrated ones and metallic photonic structure integrated ones, are reviewed. The active materials include 2D materials, quantum wells, quantum dots, and carbon nanotubes.