title: Optical trapping and alignment of single gold nanorods by using plasmon resonances.
abstract: We demonstrate three-dimensional trapping and orientation of individual Au nanorods by using laser light slightly detuned from their longitudinal plasmon mode. Detuning to the long-wavelength side of the resonance allows stable trapping for several minutes, with an exponential dependence of trapping time on laser power (consistent with a Kramer's escape process). Detuning to the short-wavelength side causes repulsion of the rods from the laser focus. Alignment of the long axis of the rods with the trapping laser polarization is observed as a suppression of rotational diffusion about the short axis.
authors.affiliation: Department of Physics, James Franck Institute, University of Chicago, Chicago, Illinois 60637, USA. pelton@uchicago.edu
authors.forename: Matthew
authors.initials: M
authors.lastname: Pelton
authors.forename: Mingzhao
authors.initials: M
authors.lastname: Liu
authors.forename: Hee Y
authors.initials: HY
authors.lastname: Kim
authors.forename: Glenna
authors.initials: G
authors.lastname: Smith
authors.forename: Philippe
authors.initials: P
authors.lastname: Guyot-Sionnest
authors.forename: Norbert F
authors.initials: NF
authors.lastname: Scherer