Dynamically Tunable Plasmon-Induced Transparency in Planar Metamaterials

We propose a planar metamaterial design to realize active manipulation of plasmon-induced transparency. Under periodic boundary condition, a surface plasmon polaritons mode is excited by a plane wave with momentum conservation at oblique incidence. Due to the destructive interference between the surface plasmon polaritons mode and induction-capacitance resonance mode, an approximate 100% transparency window is produced at large incident angles. Simply by varying the incident angle, the plasmon-induced transparency features can be dynamically tuned. At the incident angle of 70°, a sharp transparency window with a bandwidth of 30 nm is obtained at 1.71 μm. The corresponding quality factor and group index are 58 and 410, respectively, which is promising for efficient plasmonic sensing, optical switching, and slow-light devices design.