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Nanooptics of molecular-shunted plasmonic nanojunctions.

ABSTRACT: Gold nanoparticles are separated above a planar gold film by 1.1 nm thick self-assembled molecular monolayers of different conductivities. Incremental replacement of the nonconductive molecules with a chemically equivalent conductive version differing by only one atom produces a strong 50 nm blue-shift of the coupled plasmon. With modeling this gives a conductance of 0.17G(0) per biphenyl-4,4'-dithiol molecule and a total conductance across the plasmonic junction of 30G(0). Our approach provides a reliable tool quantifying the number of molecules in each plasmonic hotspot, here <200.

SUBMITTER: Benz F

PROVIDER: S-EPMC4312133 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Nanooptics of molecular-shunted plasmonic nanojunctions.

Benz Felix F Tserkezis Christos C Herrmann Lars O LO de Nijs Bart B Sanders Alan A Sigle Daniel O DO Pukenas Laurynas L Evans Stephen D SD Aizpurua Javier J Baumberg Jeremy J JJ

Nano letters 20141216 1

Gold nanoparticles are separated above a planar gold film by 1.1 nm thick self-assembled molecular monolayers of different conductivities. Incremental replacement of the nonconductive molecules with a chemically equivalent conductive version differing by only one atom produces a strong 50 nm blue-shift of the coupled plasmon. With modeling this gives a conductance of 0.17G(0) per biphenyl-4,4'-dithiol molecule and a total conductance across the plasmonic junction of 30G(0). Our approach provides ...[more]

PMID: 25494169

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