Nanooptics of Molecular-Shunted Plasmonic Nanojunctions
Felix Benz(University of Cambridge), Christos Tserkezis(Material Physics Center), Lars O. Herrmann(University of Cambridge), Bart de Nijs(University of Cambridge), Alan Sanders(University of Cambridge), Daniel O. Sigle(University of Cambridge), Laurynas Pukenas(University of Leeds), Stephen D. Evans(University of Leeds), Javier Aizpurua(Material Physics Center), Jeremy J. Baumberg(University of Cambridge)
Cited by 183Open Access
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.