Optical excitation and detection of vapor bubbles around plasmonic nanoparticles.

Laser-induced generation of the vapor bubbles in water around plasmonic nanoparticles was experimentally studied with optical scattering methods. Nanoparticle-generated bubbles temporally and spatially localize laser-induced thermal field and also amplify optical scattering relatively to that of gold nanoparticles. Bubble lifetimes and threshold fluencies were determined as functions of the laser (pulse duration, fluence, inter-pulse interval), nanoparticle (size, shape, aggregation state) and sample chamber parameters so to optimize bubble generation around plasmonic nanoparticles. Nanoparticle-generated bubbles are suggested as nano-scaled optical sensors and sources of localized thermal and mechanical impact.