Wang Neng, Lu Wanli, Ng Jack, Lin Zhifang
Opt Lett. 2014 Apr 15;39(8):2399-402. doi: 10.1364/OL.39.002399.
It is known that core-shell subwavelength nanoparticles consisting of a dielectric shell and a metallic core can simultaneously support electric and magnetic dipolar resonances, which enhance forward scattering and suppress backward scattering. This creates favorable conditions for optical tractor beam applications. Using the generalized Lorenz-Mie theory and Maxwell stress tensor formulation, we demonstrate how optical pulling forces can be induced and optimized by first-order Bessel beams with appropriate polarization. The transverse stability of the core-shell nanoparticle under ambient damping is also verified by linear stability analysis and dynamical simulation.
众所周知，由电介质壳层和金属核组成的核壳亚波长纳米粒子能够同时支持电偶极和磁偶极共振，这增强了前向散射并抑制了后向散射。这为光学牵引光束应用创造了有利条件。利用广义洛伦兹-米氏理论和麦克斯韦应力张量公式，我们证明了具有适当偏振的一阶贝塞尔光束如何能够诱导和优化光学拉力。通过线性稳定性分析和动力学模拟，还验证了核壳纳米粒子在环境阻尼下的横向稳定性。
