Optical and fluidic applications of wavelength multiplexed plasmonic nanoparticles as localized heat sources

摘要

Plasmonic nanoparticles efficiently convert light energy to thermal energy at their resonance. This effect is utilized to demonstrate localized heating within a microfluidic channel coated by these nanoparticles. Demonstrations are shown with gold and silver nanoparticles and possibilities of multiplexing are discussed.Plasmonic nanoparticles are interesting at their resonance due to their high absorption cross sections. [1] This absorption has been used to various purposes such as waveguides, surface-enhanced Raman scattering, second harmonic generation, near-filed probes, nanoscale lasers, left-handed materials, and photothermal therapy. [2] Specifically interesting is the photothermal effect, the conversion of light energy to thermal energy within the plasmonic nanoparticle. This can be used in several ways such as biosensing, flow manipulation, particle manipulation, and molecular trapping. [2] In this paper, we will use these nanoparticles as localized heat sources to demonstrate several interesting optical and/or fluidic properties, show its compatibility with soft lithography techniques using polydimethylsiloxane (PDMS) and extend its capability to do arbitrary three-dimensional surfaces in coating walls and bottom of a PDMS channel.