Optical forces are being used with increasing frequency to immobilize nanomaterials on substrates with desired configurations and patterns. It is a contact-less tool so there is little to no physical damage to samples.   In this poster, we present an efficient approach to deposit electrodynamically coupled metallic nanoparticle arrays on chemically modified substrates by a combination of optical trapping and electrodynamic inter-particle forces for spatial guidance.  Chemically tuning the nanoparticle-surface interactions to be appropriately repulsive to spontaneous deposition allows the optical trapping forces to be the sole determinant of deposition. The deposited patterns show preferred separations between nanoparticles when positioning the optical line trap with various inter-column separations. Overall, the findings suggest a meso-scale interaction attributed to optical field-induced optical binding forces. Electrodynamics simulations of the inter-particle interactions corroborate optical binding as accounting for our experimental results.  This �optical printing� method is a promising approach to effectively fabricate dense nanoparticle arrays on meso-scales with nanoscale positional precision.

Optical printing of electrodynamically coupled metallic nanoparticle chains

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.