Tunable Triple Plasmon-Induced Transparencies in Dual T-Shaped Cavities Side-Coupled Waveguide

In this letter, all-optical dynamically tunable triple plasmon-induced transparency responses are proposed in an ultracompact plasmonic structure, which comprises dual T-shaped resonators side-coupled to a metal–insulator–metal waveguide in the near infrared range. High tunability in magnitudes of optical channel 1 and optical channel 3 can be achieved, when the waveguide is filled with a nonlinear optical Kerr material, while that of optical channel 2 remains the same approximately. It is also possible to realize low-power tunability in central wavelengths of all-optical channels, when the resonators are covered by a single graphene layer under excitation with a pump light at various intensities. This letter opens up the possibility for the realization of a dynamically tunable multichannel filter or slow light devices in highly integrated optical circuits.