Plasmonic 2D infrared photodetectors: leveraging near-field enhancement and plasmon-induced hot-carrier transfer

Plasmonic two-dimensional (2D) infrared photodetectors have received extensive attention for achieving outstanding photoelectric performance, which demonstrates potential to overcome the inherent limitations of conventional infrared detection technologies. Integrating plasmonic nanostructures with 2D materials allows these devices to use localized surface plasmon (LSP) resonances to enhance light absorption. Meanwhile, the decay of LSPs can generate hot carriers that can be injected into the 2D material to generate photocurrent. We summarize the recent progress of plasmonic 2D infrared photodetectors, covering key materials, fabrication techniques, plasmonic hot-carrier dynamics, photodetection mechanisms, and device designs. It also outlines future directions in material and interface engineering, device architecture, scalable fabrication, and system-level integration to advance next-generation plasmonic infrared optoelectronic technologies.