Multifunctional space-time-coding amplitude modulated graphene metasurfaces

Realizing multifunctional applications in a simple structure has garnered great interest. For this purpose, we theoretically and numerically demonstrate that an easy-to-fabricate metasurface, consisting of an array of graphene ribbons, can perform various functionalities. Due to the strong light–matter interaction caused by graphene localized surface plasmons (GLSPs), the proposed structure can be used as a sensor. In addition, by applying proper space-time-coding sequences to the gated graphene ribbons controlled by the field programmable gate array, there is immediate access to various amplitude profiles for different applications, including multiband absorbers (or reflectors) and harmonic beam steering. Compared with conventional GLSP-based devices, a combination of graphene with coding sequences offers an effective method to instruct multifunctional devices.