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Off-Resonant Two-Photon Absorption Cross-Section Enhancement of an Organic Chromophore on Gold Nanorods.

ABSTRACT: Surface-plasmon-initiated interference effects of polyelectrolyte-coated gold nanorods on the two-photon absorption of an organic chromophore were investigated. With polyelectrolyte bearing gold nanorods of 2,4,6 and 8 layers, the role of the plasmonic fields as function of distance on such effects was examined. An unusual distance dependence was found: enhancements in the two-photon cross-section were at a minimum at an intermediate distance, then rose again at a further distance. The observed values of enhancement were compared to theoretical predictions using finite element analysis and showed good agreementdue to constructive and destructive interference effects.

SUBMITTER: Sivapalan ST

PROVIDER: S-EPMC3653337 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature

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Off-Resonant Two-Photon Absorption Cross-Section Enhancement of an Organic Chromophore on Gold Nanorods.

Sivapalan Sean T ST Vella Jarrett H JH Yang Timothy K TK Dalton Matthew J MJ Haley Joy E JE Cooper Thomas M TM Urbas Augustine M AM Tan Loon-Seng LS Murphy Catherine J CJ

The journal of physical chemistry letters 20130301 5

Surface-plasmon-initiated interference effects of polyelectrolyte-coated gold nanorods on the two-photon absorption of an organic chromophore were investigated. With polyelectrolyte bearing gold nanorods of 2,4,6 and 8 layers, the role of the plasmonic fields as function of distance on such effects was examined. An unusual distance dependence was found: enhancements in the two-photon cross-section were at a minimum at an intermediate distance, then rose again at a further distance. The observed ...[more]

PMID: 23687561

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