摘要
Strong plasmonic focal spots, excited by radially polarized light on a smooth thin metallic film, have been widely applied to trap various micro-and nano-sized objects. However, the direct transmission part of the incident light leads to the scattering force exerted on trapped particles, which seriously affects the stability of the plasmonic trap.Here we employ a novel perfect radially polarized beam to solve this problem. Both theoretical and experimental results verify that such a beam could strongly suppress the directly transmitted light to reduce the piconewton scattering force, and an enhanced plasmonic trapping stiffness that is 2.6 times higher is achieved in experiments.The present work opens up new opportunities for a variety of research requiring the stable manipulations of particles.
Strong plasmonic focal spots, excited by radially polarized light on a smooth thin metallic film, have been widely applied to trap various micro- and nano-sized objects. However, the direct transmission part of the incident light leads to the scattering force exerted on trapped particles, which seriously affects the stability of the plasmouic trap. Here we employ a novel perfect radially polarized beam to solve this problem. Both theoretical and experimental results verify that such a beam could strongly suppress the directly transmitted light to reduce the piconewton scattering force, and an enhanced plasmouic trapping stiffness that is 2.6 times higher is achieved in experiments. The present work opens up new opportunities for a variety of research requiring the stable manipulations of particles. 2018 Chinese Laser Press
基金
National Natural Science Foundation of China(NSFC)(61427819,61490712,91750205,U1701661,61605117,11604219)
National Key Basic Research Program of China(973)(2015CB352004)
National Key Research and Development Program of China(2016YFC0102401)
Leading Talents Program of Guangdong Province(00201505)
Natural Science Foundation of Guangdong Province(2016A030312010,2016A030310063,2017A030313351)
Science and Technology Innovation Commission of Shenzhen(KQTD2015071016560101,KQTD2017033011044403,ZDSYS201703031605029,JCYJ2017818144338999)
Excellent Young Teacher Program of Guangdong Province(YQ2014151)
China Post-doctoral Science Foundation(2017M612722)