Open AccessOptically controlled interparticle distance tuning and welding of single gold nanoparticle pairs by photochemical metal deposition
Author(s) -
Thomas Härtling,
Yury Alaverdyan,
Andreas Hille,
M. T. Wenzel,
Mikael Käll,
Lukas M. Eng
Publication year - 2008
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.16.012362
Subject(s) - materials science , plasmon , surface plasmon resonance , electron beam lithography , optics , particle (ecology) , localized surface plasmon , lithography , nanoparticle , molecular physics , deposition (geology) , optoelectronics , nanotechnology , resist , chemistry , physics , paleontology , oceanography , layer (electronics) , sediment , geology , biology
We report on the in-situ controlled tuning of the particle gap in single pairs of gold nanodisks by photochemical metal deposition. The optically induced growth of nanodisk dimers fabricated by electron beam lithography leads to a decrease of the interparticle gap width down to 0 nm. Due to the increasing particle size and stronger plasmonic coupling, a smooth redshift of the localized surface plasmon (LSP) resonances is observed in such particle pairs during the growth process. The interparticle gap width, and hence the LSP resonance, can be tuned to any desired spectral position. The experimental results we obtain with this nanoscale fabrication technique are well described by the so-called plasmon ruler equation. Consequently, both the changes in particle diameter as well as in gap width can be characterized in-situ via far-field read-out of the optical properties of the dimers.