Effects of mutual coupling in dual-resonance metamaterials

TL;DR

This paper investigates how mutual coupling affects dual-resonance metamaterials, revealing resonance shifts and weakening, which are crucial for designing broadband and spatially variable metamaterials.

Contribution

It provides a combined simulation and experimental analysis of mutual coupling effects in dual-resonance metamaterials, highlighting inductive coupling as a key factor.

Findings

Resonance frequencies shift significantly when resonators are spectrally close

Mutual coupling weakens the resonances

Inductive coupling is identified as the primary cause

Abstract

This Letter presents an investigation on the effects of mutual coupling in a metamaterial comprising two sets of electric-LC (ELC) resonators with different resonance frequencies. Through simulation and experiment, it is found that the two resonances experience significant shifting and weakening as they become spectrally close. An equivalent circuit model suggests that inductive coupling among the two resonator sets is a primary cause of the change in the resonance properties. This study is fundamental to designing metamaterials with an extended bandwidth or spatially variable response.