Light absorption enhancement of graphene using a narrow grooved metasurface

Light absorption enhancement of graphene is achieved by using the narrow grooved metasurface. The operational principle of the structure is to utilize the surface plasmon resonance confined in the narrow groove, and a simplified cavity resonance model can be used to estimate the location of the absorption peak. By integrating the graphene sheet with a multi-grooved metasurface, an angle-insensitive light absorption enhancement of graphene covering the whole visible spectrum can be obtained. In addition, broadband light absorption enhancement of graphene is robust to the variations of the structure parameters, the broad absorption band can be maintained even the number of the groove is altered.