Simulation and design of dual-band quantum dot infrared photodetector based on metal grating structure

Quantum dot infrared photodetectors (QDIP) have a weak ability to capture light, which limits the further improvement of absorptivity certain extent. Since localized surface plasmon resonance (LSPR) can effectively couple optical radiation energy and result in significant field enhancement effect near-field range, it is introduced improve QDIP. Concretely, strip metal grating structure coupled active region traditional QDIP, reflective layer added at bottom QDIP by using metal–semiconductor–metal structure. The simulation results show that addition optimized make photon reach more than 90% both frequency bands 37.5 48.5 THz, coupling characteristics LSPR are studied analysis electric distribution provide theoretical guidance for combination