LAUSR

Abstract The electrical voltage control of triple Fano resonance via a plasmonic waveguide system which is composed of a rectangular resonator coupled with a defect cavity is presented. A liquid crystal material is incorporated in the rectangular resonator to tune the Fano resonance by the applied voltage. Two dimensional finite difference time domain method is used to calculate the transmission and field distribution. The triple Fano resonance are found to originate from different mechanisms. FR3 is originated from the interference between the horizontal and vertical resonance mode in the rectangular resonator. FR2 is induced by the asymmetry of the proposed structure. And FR1 is attributed to the inherent resonant mode in the slot defect. The FR1 can be tuned by changing the slot defect’s size or position. The asymmetrical Fano linestyle can be tuned by the rectangular resonator”s size or the applied voltage. The F O M * (figure of merit) and sensitivity of the FR2 can be up to 100 and, respectively. The proposed plasmonic structure may have application in slow light device, nanoscale filter, refractive index sensor and other related plasmonic devices.