title: Control of diffusion of nanoparticles in an optical vortex lattice.
abstract: A two-dimensional periodic optical force field, which combines conservative dipolar forces with vortices from radiation pressure, is proposed in order to influence the diffusion properties of optically susceptible nanoparticles. The different deterministic flow patterns are identified. In the low-noise limit, the diffusion coefficient is computed from a mean first passage time and the most probable escape paths are identified for those flow patterns which possess a stable stationary point. Numerical simulations of the associated Langevin equations show remarkable agreement with the analytically deduced expressions. Modifications of the force field are proposed so that a wider range of phenomena could be tested.
authors.affiliation: Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain.|Departamento Física de Materiales, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Ivar
authors.initials: I
authors.lastname: Zapata
authors.affiliation: Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Delgado-Buscalioni
authors.affiliation: Donostia International Physics Center (DIPC), Paseo Manuel Lardizabal 4, 20018 Donostia-San Sebastian, Spain.|IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain.
authors.forename: Juan José
authors.initials: JJ
authors.lastname: Sáenz