Multiple Fano resonances in metal–insulator–metal waveguide with umbrella resonator coupled with metal baffle for refractive index sensing |
(a) Transmission spectra of the MIM structure changing with length of horizontal resonator L1, (b) transmission spectra of two Fano resonance peaks FR4 and FR5 (wavelength range from 1250 nm to 1550 nm), and (c) resonance wavelengths of the two Fano resonance peaks FR4 and FR5 changing with horizontal cavity length L1. |