Tunable absorption enhancement in electric split-ring resonators-shaped graphene arrays

In this paper, we propose a wavelength-tunable absorber consisting of electric split-ring resonators (eSRRs)-shaped graphene arrays deposited on a SiO2/Si substrate in the far-infrared and terahertz regions. The simulation results exhibit that two resonance modes are supported by the structure. In terms of the resonance at longer wavelength, the light absorption declines while the period a or length L increases. However, absorption contrarily improves with enlargement of incident angle under the transverse magnetic (TM) polarization. And in terms of resonance at shorter wavelengths, absorption enhances with increasing length L and incident angle theta. Generally, the light absorption enhances with Fermi level E-F of graphene, accompanied by blue shift. The aforementioned results unquestionably provide a distinctive source of inspiration for how to design and manufacture devices related to absorption such as filters, spatial light modulator and sensors.