Dielectric Sensing by Babinet’s Principle in Plasmonics

The engineering of localized surface plasmon (LSP) resonances in plasmonic structures has led to advances in fields such as chemistry, medicine, and sensing. For the latter case, LSP resonances in metallic micro-/nano structures are particularly important due to these resonances being sensitive to external changes in their near-field, such as the presence of nearby dielectrics. In this communication, complementary metal-dielectric plasmonic structures designed by exploiting Babinet’s principle are studied and designed to act as plasmonic sensors of thin film dielectrics. We make use of metallic plasmonic dimers and their complementary structures (holes on a thin metallic screen) and provide an in-depth study of their performance in terms of their field distribution and sensitivity.