title: Plasmon-enhanced total-internal-reflection fluorescence by momentum-mismatched surface nanostructures.
abstract: We investigate optimum plasmon-enhanced total-internal-reflection fluorescence imaging by metallic thin films and nanostructures. The enhancement is based on the mismatch between the conditions of plasmon resonance and maximal near-field intensity. We have calculated plasmon-associated near-field and far-field characteristics using rigorous coupled-wave analysis. Near-field intensity was experimentally measured with fluorescent beads on silver thin films, nanogratings, and nanoislands. The results for nanostructure-based plasmon excitation confirm that momentum mismatching when exciting plasmons can increase the consequent emission of fluorescence substantially. The improvement can be critical depending on the specific structure.
authors.affiliation: Program for Nanomedical Science and Technology, Yonsei University, Seoul, Korea 120-749.
authors.forename: Kyujung
authors.initials: K
authors.lastname: Kim
authors.forename: Youngjin
authors.initials: Y
authors.lastname: Oh
authors.forename: Kyungjae
authors.initials: K
authors.lastname: Ma
authors.forename: Eunji
authors.initials: E
authors.lastname: Sim
authors.forename: Donghyun
authors.initials: D
authors.lastname: Kim