Optically controlled interparticle distance tuning and welding of single gold nanoparticle pairs by photochemical metal deposition

• 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.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Annan teknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Other Engineering and Technologies (hsv//eng)

Keyword

DIMERS

SPECTROSCOPY

LIGHT-SCATTERING

ENHANCED RAMAN-SCATTERING

MOLECULES

FIELD

PARTICLE PAIRS

PLASMON RESONANCES

CLUSTERS

Publication and Content Type

art (subject category)

ref (subject category)