title: Backward transport of nanoparticles in fluidic flow.
abstract: We demonstrate a backward transport of polystyrene (PS) particles (713-nm in diameter) in a pressure-driven fluidic flow using an optical fiber with a diameter of 710 nm. When a light of 980-nm wavelength was launched into the fiber in the opposite direction of the flow, the PS particles near the fiber were attracted onto the fiber and transported along the propagation direction of the light. The relationship between the velocity of the transported PS particles and the velocity of the flow at different input optical powers was investigated. Numerical analyses on both the optical field and the fluid field were carried out. The particle-size dependence of backward transport capability has also been investigated.
authors.affiliation: State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-Sen University, Guangzhou 510275, China.
authors.forename: Chong
authors.initials: C
authors.lastname: Xu
authors.forename: Hongxiang
authors.initials: H
authors.lastname: Lei
authors.forename: Yao
authors.initials: Y
authors.lastname: Zhang
authors.forename: Baojun
authors.initials: B
authors.lastname: Li
mesh_terms: D005336:Fiber Optic Technology / Q000295:instrumentation*; D008027:Light; D044085:Microfluidics / Q000295:instrumentation*; D009038:Motion; D053758:Nanoparticles / Q000737:chemistry* / Q000528:radiation effects* / Q000648:ultrastructure; D052898:Optical Tweezers