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Radiation channels close to a plasmonic nanowire visualized by back focal plane imaging.

ABSTRACT: We investigated the angular radiation patterns, a key characteristic of an emitting system, from individual silver nanowires decorated with rare earth ion-doped nanocrystals. Back focal plane radiation patterns of the nanocrystal photoluminescence after local two-photon excitation can be described by two emission channels: excitation of propagating surface plasmons in the nanowire followed by leakage radiation and direct dipolar emission observed also in the absence of the nanowire. Theoretical modeling reproduces the observed radiation patterns which strongly depend on the position of excitation along the nanowire. Our analysis allows us to estimate the branching ratio into both emission channels and to determine the diameter-dependent surface plasmon quasi-momentum, important parameters of emitter-plasmon structures.

SUBMITTER: Hartmann N

PROVIDER: S-EPMC3925822 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature

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Radiation channels close to a plasmonic nanowire visualized by back focal plane imaging.

Hartmann Nicolai N Piatkowski Dawid D Ciesielski Richard R Mackowski Sebastian S Hartschuh Achim A

ACS nano 20131016 11

We investigated the angular radiation patterns, a key characteristic of an emitting system, from individual silver nanowires decorated with rare earth ion-doped nanocrystals. Back focal plane radiation patterns of the nanocrystal photoluminescence after local two-photon excitation can be described by two emission channels: excitation of propagating surface plasmons in the nanowire followed by leakage radiation and direct dipolar emission observed also in the absence of the nanowire. Theoretical ...[more]

PMID: 24131299

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