Optical trapping of micrometer-sized dielectric particles by cylindrical vector beams.

Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Aoba-ku, Sendai 980-8577, Japan.
Optics Express (Impact Factor: 3.55). 05/2010; 18(10):10828-33. DOI: 10.1364/OE.18.010828
Source: PubMed

ABSTRACT Single-beam optical trapping of micrometer-sized dielectric particles is experimentally demonstrated using radially and azimuthally polarized beams. The axial and transverse optical trapping efficiencies of glass and polystyrene beads suspended in water are measured. The radially polarized beam exhibited the highest trapping efficiency in the axial direction due to the p polarization of the radial polarization on the particle surface. On the other hand, the azimuthally polarized beam had a higher transverse trapping efficiency than the radially polarized beam. These results are consistent with numerical predictions.

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