Using Babinet’s principle in plasmonics for dielectric sensing

Plasmonic structures that exhibit localized surface plasmon (LSP) resonances have been exploited in multiple applications including sensing, medicine, and chemistry. LSPs resonances appearing in, for instance, periodic/aperiodic rods or spheres have been recently used for sensing due to the fact that such resonances are sensitive to local external variations such as changes in the refractive index of a dielectric placed on top of them. In this communication, we make use of complementary plasmonic structures (exploiting the Babinet’s principle) consisting of metal-dielectric cylindrical components to study their performance as dielectric film sensors. An in-depth comparison of the complementary structures with the original plasmonic configurations is carried out demonstrating the advantages/disadvantages of each design.