High-Q Plasmonic Resonances: Fundamentals and Applications

Subwavelength confinement of light with plasmonics is promising for nanophotonics and optoelectronics. However, it is nontrivial to obtain narrow plasmonic resonances due to the intrinsically high optical losses and radiative damping in metallic structures. In this review, a thorough summary of the recent research progress on achieving high-quality (high-Q) factor plasmonic resonances is provided, emphasizing the fundamentals and six resonant mode types, including surface lattice resonances, multipolar resonances, plasmonic Fano resonances, plasmon-induced transparency, guided-mode resonances, and Tamm plasmon resonances. The applications of high-Q plasmonic resonances in spectrally selective thermal emission, sensing, single-photon emission, filtering, and band-edge lasing are also discussed.