Tunable triple-band negative permeability metamaterial consisting of single-loop resonators and ferrite

Abstract

We numerically propose a novel tunable metamaterial with triple bands of negative permeabilities. This metamaterial is composed of an array of single-loop resonators (SLRs) and ferrite slabs, where the SLRs provide two magnetic resonances while the ferrite slabs under an applied dc magnetic bias give rise to the third magnetic resonance. By adjusting the intensity of the dc magnetic bias, it is able to tune all the three magnetic resonances. The -negative features of these resonant bands are investigated by retrieving the constitutive parameters from simulated -parameters. The results in this paper open a new approach for designing tunable multiband metamaterials, which is sure to find extensive applications in fields such as tunable multiband notched ultra-wideband (UWB) antennas, tunable multiband perfect lens, and tunable multiband absorbers.