Sensor based on Fano resonances of plane metamaterial with narrow slits

- The plasmonic nanostructure composed of narrow slits and nano hole pairs were designed.
- The optical properties were investigated experimentally and numerically.
- The Fano resonances were found on the compound nanostructure.
- The results have potential applications in sensing and weak signal detection.

The optical properties of a composite metamaterial composed of narrow slits and nano hole pairs have been investigated experimentally and numerically. The strength of the transmission peak originating from the interference between the coupled surface plasmon polaritons (SPP) of the narrow slit and the SPP modes of the hole array is modulated by the degree of symmetry breaking. Some SPP modes can be inhibited by controlling the spacer layer thickness. Our metamaterial has potential applications in sensing and weak signal detection.