A Novel Tunable Absorber Based on Vertical Graphene Strips

A novel type of graphene strips based three-dimensional absorber is proposed, which shows a dynamic tunability of absorbing band. The proposed structure is based on a two-dimensional array of vertical graphene strips with dielectric substrates beneath them. An absorption peak is obtained at the plasmon resonant frequency of the graphene strips. The relationship between the plasmon resonant frequency and the dimensions of absorber obeys the scaling law. Furthermore, by using the trapezoid graphene strips together with the hybrid electrostatic biases, the absorbing bandwidth can be improved significantly. In addition, the absorber shows a good stability with various incident angles and polarizations.