Guided mode resonance in planar metamaterials consisting of two ring resonators with different sizes

We proposed and experimentally investigated a two-ring-resonator composed planar hybrid metamaterial (MM), in which the spectra of guided mode resonance (GMR) and Fano resonance or EIT-like response induced by coherent interaction between MM resonance and GMR can be easily controlled by the size of the two rings in the terahertz regime. Furthermore, a four-ring-resonator composed MM for polarization-insensitive GMRs was demonstrated, where GMRs of both TE and TM modes are physically attributed to the diffraction coupling by two +/- 45 degrees tilting gratings. Such kind of device has great potential in ultra-sensitive label-free sensors, filters, or slow light based devices.