Optical excitation and detection of vapor bubbles around plasmonic nanoparticles

Laser-induced generation of vapor bubbles in water around plasmonic nanoparticles was experimentally studied by optical scattering methods. Nanoparticle-generated bubbles spatially localize a laser-induced thermal field and also amplify the optical scattering relatively to that by gold nanoparticles. Bubble lifetimes and threshold fluencies were determined as functions of the parameters of a laser ( pulse duration, fluence, interpulse interval), nanoparticle ( size, shape, aggregation state), and of the sample chamber so as to optimize the conditions of bubble generation around plasmonic nanoparticles. Nanoparticle-generated bubbles are suggested as nano-sized optical sensors and sources of localized thermal and mechanical impact. (C) 2009 Optical Society of America