Abstract:

 In the paper, Fano resonances in a planar metamaterial with asymmetrically split rings are investigated
using the finite element method. Excited surface current distributions are presented. The transmission
spectrum of the metamaterial is also fitted based on the Fano formula. The electromagnetic response of each
metallic ring is studied individually. It is found that the Fano resonances are due to the coupling between
two asymmetric metallic resonators. Further, effects of the structural parameters on the Fano resonance are
analyzed. Finally, dependence of Fano resonance on polarization rotation angles of the incident electromagnetic
waves is studied. Simulation results reveal that polarization rotation angles of incident electromagnetic waves
provides an easy approach of tuning the performance of metamaterials.

Key words: metamaterials, split-ring resonator, Fano resonance, surface current, transmission