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arXiv · 2004.13995

Off-axis optical trapping and transverse spinning of metallic microparticles with a linearly polarized Gaussian beam

Yansheng Liang·Zhaojun Wang·Ming Lei
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Abstract

Optical trapping of metallic microparticles remains a big challenge because of the strong scattering and absorption of light by the particles. In the paper, we report a new mechanism for stable trapping of metallic microparticles by using a tightly focused linearly polarized Gaussian spot. We theoretically and experimentally demonstrated that metallic microparticles were confined off the optical axis by such a trap. In the meanwhile, transverse spinning motion occurred as a consequence of the asymmetric force field acting on the particle by the trap. The off-axis trapping and transverse spinning of metallic microparticles provide new manners for the manipulation of metallic microparticles. The works reported in this paper are also of significance for a better understanding of the mechanical interaction between light and metallic particles.

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Yansheng Liang, Zhaojun Wang, Ming Lei. 2020-04-29. Off-axis optical trapping and transverse spinning of metallic microparticles with a linearly polarized Gaussian beam. https://arxiv.org/abs/2004.13995

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