Dual-band plasmon induced transparency metamaterial based on multi-quasi-bright modes

Abstract

In general, we have proposed an innovative dual-band plasmon-induced transparency (PIT) metamaterial (MM) consists of a metal cut-wire (CW) and a parallel cut-wire-pair (CWP) separated by a dielectric spacer, which behaves as a bright mode and multi-quasi-bright modes separately. The dual-band transparency widow can be observed in the microwave region due to the near-field coupling among the bright mode and multi-quasi-bright modes, numerically and experimentally investigated. It is found that a strong magnetic resonance has been introduced in our PIT structure due to the local magnetic interaction between the double-layered CWs; therefore, an extensive group index over 680 can be obtained. Finally, the dual-band PIT MM properties are investigated numerically and theoretically, using equivalent circuit model (ECM) and coupled oscillator model (COM), respectively.