Multiple Fano resonances in metal–insulator–metal waveguide with umbrella resonator coupled with metal baffle for refractive index sensing
Qi Yun-Ping1, 3, †, Wang Li-Yuan1, Zhang Yu1, Zhang Ting1, Zhang Bao-He1, Deng Xiang-Yu1, Wang Xiang-Xian2
       

(a) Transmission spectra for three different refractive indexes, and (b) FOM* varying with wavelength of the whole system.