Polychromatic nanofocusing of surface plasmon polaritons

Abstract

We introduce the concept of polychromatic plasmonics and suggest a broadband plasmonic lens for nanofocusing of surface plasmon polaritons. The lens employs a parabolically modulated metal-dielectric-metal structure. This plasmonic lens has a bandwidth of more than an optical octave, thus opening new opportunities for broadband plasmonic applications.