Optical refractive nanosensor with planar resonators metamaterial

We numerically investigated the optical properties of planar resonators metamaterial that exhibits two narrow transmitted dips with quality factors of 23 and 50 in the optical regions. The results show that, both of the two resonances reveal a distinct plasmon shift with respect to a small fluctuation in the refractive index of the surrounding medium, and calculated average refractive index sensitivities are 900 nm/RIU and 493 nm/RIU, and corresponding figure of merits of two modes are 16 and 32 in vacuum, respectively. The sensing performance can be improved by changing the geometric parameters of planar metamaterial due to the plasmon modes coupling effect, which offer an excellent potential for optical nanosensing applications.