title: Optical force enhancement and annular trapping by plasmonic toroidal resonance in a double-disk metastructure.
abstract: Optical forces can be enhanced by surface plasmon resonances with various interesting characteristics. Here, we numerically calculated the optical forces enhanced by a new kind of toroidal dipolar resonance in a double-disk metastructure. The results show that this kind of optical force is competitive with ordinary plasmonic forces and typically can reach-182.5pNμm2mW-1. Influences of geometric parameters are discussed for the enhancement characteristic of optical force. Finally, we make a contrastive investigation on the optical trapping characteristic on a 5-nm-diameter nanoparticle, and show that the unique annular trapping region can be utilized for nanoscale applications.
authors.forename: Ren-Chao
authors.initials: RC
authors.lastname: Jin
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.forename: Ying-Hua
authors.initials: YH
authors.lastname: Wang
authors.forename: Ming-Jie
authors.initials: MJ
authors.lastname: Zhu
authors.forename: Jia-Qi
authors.initials: JQ
authors.lastname: Li
authors.forename: Zheng-Gao
authors.initials: ZG
authors.lastname: Dong