A Reconfigurable Sensing Structure for Fast Optical Modulation by Graphene in Critically Coupled Photonic Crystal Cavities

We propose a fast optical reconfigurable intelligent surface (FORIS) whose optical properties can be modulated by a thin layer of graphene with critically coupled photonic crystal slab (G-PCS) structure. By tuning the critical coupling condition between the photonic crystal modes and the absorptive graphene monolayer, perfect reflection/absorption of probing light beams can be achieved with operation speed at GHz level. The proposed reconfigurable structure has potential applications in remote sensing, free-space communications, LiDAR, active sensing, and imaging.