The generation of multiple electric and magnetic Fano resonances in the prefect ring-triple arcs ring nanostructure

The electromagnetic field enhancement, multiple electric and magnetic Fano resonances in perfect ring-triple arcs ring (PR-TAR) nanostructure are studied by using finite element method. In this nanostructure, electric and magnetic Fano resonances can be promoted as a result of the coupling between dark modes of the perfect ring (PR) and bright modes of the triple arcs ring (TAR). New multiple electric and magnetic Fano resonances are obtained by changing the central angle or the thickness of the up arc. Multiple new resonance modes can be generated by offsetting the center of the TAR. According to the calculation results, the electric and magnetic fields are both enhanced greatly. The highest electric and magnetic field enhancements reached 409 and 48.7, respectively. These characteristics of the PR-TAR nanostructure have potential applications on the propagation of lowloss plasmons, surface enhanced plasmon spectroscopy, multi-wavelength spectrometer and multicontrol Fano switch.