Optical guiding of absorbing nanoclusters in air

We introduce a novel approach for all-optical trapping and manipulation of absorbing aerosol particles based on a photophoretic force. We demonstrate experimentally, in open air, the robust three-dimensional guiding of agglomerates of carbon nanoparticles with the size spanned for two orders of magnitude, from 100 nanometers to 10 microns, over the distances of a few millimeters, as well as their acceleration up to velocities of 1 cm/s and simultaneous trapping of a large number of particles.
Comment: 12 pages including 8 figures. First presented at SPIE Conference 7038 on Optical Trapping and Optical Micromanipulation V, San Diego, USA, 13 August 2008, paper 7038-69