Active plasmonic band stop filters based on graphene metamaterial at THz wavelengths.
Active plasmonic band stop filters based on single and double layer doped graphene metamaterials at the THz wavelengths are proposed and investigated numerically by using the finite difference time domain (FDTD) method. The metamaterial unit cell structure is composed of two parallel graphene nanoscale ribbons. Simulated results exhibit that significant resonance wavelength shifts can be achieved with a slight variation of the doping concentration of the graphene ribbons. Besides, the asymmetry double layer graphene metamaterial device has two apparent filter dips while the symmetry single double layer and asymmetry single layer graphene metamaterial devices just only one. The metamaterials with symmetry single layer and asymmetry double layer graphene can be used as a high sensitivity refractive sensor with the sensitivity up to 5100 nm/RIU and a two circuit switch, respectively. These prospects pave the way towards ultrafast active graphene based plasmonic devices for THz applications.
Optics express