Polarization-insensitive resonances with high quality-factors in meta-molecule metamaterials

Achieving narrow resonance is an area of interest within the field of metamaterials. However, only a few studies have investigated the polarization-insensitive resonances. A general principle for improving quality Q-factor of a sharp resonance is still unclear. In this work, we proposed a kind of planar meta-molecule metamaterials, which can exhibit polarization-insensitive resonance with high Q-factor. The proposed structures have a unit cell consisting of four arrayed ring resonant elements with two different sizes. Moreover, the investigation on surface current and two referential simulated structures confirm a principle for improving Q-factor.