Double Fano resonances in a composite metamaterial possessing tripod plasmonic resonances

Double Fano resonances are observed in a planar composite metamaterial possessing tripod plasmonic resonances, where a common subradiant driven oscillator is coupled with two superradiant oscillators. As a classical analogue of four-level tripod atomic system, the extinction spectrum of the composite metamaterial exhibits a coherent effect based on double Fano resonances. It is shown that a transfer of the absorbed power between two orthogonal superradiant oscillators is mediated by a common subradiant oscillator.