Long-Wave Infrared Graphene Photodetectors for Polarization Detection and Gas Sensing

Graphene has attracted great interest for integrated photonic platforms in the long-wave infrared (LWIR) due to the capability of on-chip integration. However, graphene suffers from weak infrared absorption and small in-plane anisotropy. Here, we propose LWIR metamaterial-mediated graphene photodetectors (MMGPDs) for polarization detection and gas sensing. Our devices demonstrate a high responsivity with low noise-equivalent power, and a subtle polarization-angle detection. Our platforms show a low limit of detection and fast dynamic response for gas sensing. Our devices show potential as a multi-functional miniaturized platforms toward environmental and biomedical monitoring.