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Highly spectral dependent enhancement of upconversion emission with sputtered gold island films.

ABSTRACT: We report a five-fold overall enhancement of upconversion emission in NaYF(4)?:?Yb/Er nanocrystals when coupled with gold island films. Spectroscopic studies show that the enhancement factors are highly dependent on the exact spectral positions and excitation power density, with a largest enhancement factor of more than 12 observed at selected spectral positions, which may be attributed to different upconversion processes involved.

SUBMITTER: Zhang H

PROVIDER: S-EPMC3236241 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature

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Highly spectral dependent enhancement of upconversion emission with sputtered gold island films.

Zhang Hua H Xu Di D Huang Yu Y Duan Xiangfeng X

Chemical communications (Cambridge, England) 20101116 3

We report a five-fold overall enhancement of upconversion emission in NaYF(4) : Yb/Er nanocrystals when coupled with gold island films. Spectroscopic studies show that the enhancement factors are highly dependent on the exact spectral positions and excitation power density, with a largest enhancement factor of more than 12 observed at selected spectral positions, which may be attributed to different upconversion processes involved. ...[more]

PMID: 21079884

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