Radiation forces analysis for gold nanoparticles in optical tweezers

Gold nanoparticles have found broad applications in nanomaterials and nanobiotechnology, but generally they are considered difficult to trap stably. In this paper, numerical studies are carried out to show that the main forces on the gold particles in optical tweezers. The results show that a stable trap for gold nanoparticles can be formed only when the parameters of laser wavelength, laser power, particle size and numerical aperture are properly selected. Keywords: gold nanoparticles, optical tweezers, gradient force, scattering/absorption force