Mb. Mohamed et al., The 'lightning' gold nanorods: fluorescence enhancement of over a million compared to the gold metal, CHEM P LETT, 317(6), 2000, pp. 517-523
Gold nanorods capped with micelles and having an aspect ratio of 2.0-5.4 ar
e found to fluoresce with a quantum yield which is over a million times tha
t of the metal. For rods of the same width, the yield is found to increase
quadratically while the wavelength maximum increases linearly with the leng
th. We assign this emission to the electron and hole interband recombinatio
n. The increase in the emission yield results from the enhancement effect o
f the incoming and outgoing electric fields via coupling to the surface pla
smon resonance in the rods. This is similar to the previously proposed fluo
rescence and the Raman enhancement on noble metal rough surfaces. (C) 2000
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