Plasmonics with a Twist: Taming Optical Tornadoes on the Nanoscale

摘要: This chapter discusses a hydrodynamics-inspired approach to trap and manipulate light in plasmonic nanostructures, which is based on steering optical powerflow around nano-obstacles. New insights into nanofocusing mechanisms are obtained by invoking an analogy of the 'photon fluid' (PF). By proper nanostructure design, PF kinetic energy can be locally increased via convective acceleration then converted 'pressure' generate localized areas high field intensity. In particular, trapped molded vortices -tornado-like circular motion power flux - connected transmission-like sequences. electromagnetic theory terms, this radiationless interference evanescent fields rather than propagating waves radiated dipoles induced nanoparticles. The resulting ability well beyond diffraction limit helps reduce dissipative losses, increase amount accumulated within nanoscale volume, activate magnetic response non-magnetic nanostructures. It also forms basis for long-range on-chip transfer/routing as active modulation switching.