Advanced functional infrared (IR) photodetectors with wavelength selectivity are promising for a wide range ofapplications, such as multicolor imaging, gas analysis and biomedical analysis. Graphene is considered to be a promisingmaterial for novel IR detectors. However, the absorption of graphene is constant at approximately 2.3% and rather small.We have developed multispectral high-performance graphene IR photodetectors using metal-insulator-metal (MIM) orsingle-layer (SL) plasmonic metasurfaces (PMs). MIM- or SL-PMs induce localized surface plasmons on their surfacesand enhance absorption at the wavelength, which can be controlled by their surface patterns, such as the period or thegaps between micropatches. The absorption of graphene with PMs was theoretically investigated for various structuralparameters. The absorption wavelength can be controlled based on plasmonic resonance by varying the surface geometryof the PMs. Graphene-based IR photodetectors with SL-PMs were fabricated by the chemical vapor deposition ofgraphene and then transferred onto the PMs. Wavelength-selective enhancement of the optical absorption and detectionby graphene could be achieved due to the effect of the PMs. The results obtained here are expected to contribute to therealization of multispectral graphene infrared image sensors.
展开▼
