Mutual coupling effects between meta-atoms for enhanced bandwidth

We analyzed theoretically and experimentally the inter-element coupling behavior between the periodic structure's so-called "meta-atoms" by varying the number of meta-atoms arranged periodically in the array. For this reason a planar metamaterial consisting of ring-shaped subwavelength periodic structures on a thin metal film was developed to exhibits a resonant transparency at the frequency of about 0.35 THz. The cross-talk between the meta-atoms due to electromagnetic multipole interferences lead to a significant change in resonance bandwidth and the quality (Q) factor. We anticipate that found coupling behavior between inter-element with subwavelength dimensions can potentially be used for a variety of applications such as filters, multi-pixel emitter and detector arrays, etc. for broad THz frequencies.