【摘要】 使用聚焦平顶光束和平顶涡旋光束,以金为例,对金属瑞利粒子辐射力和俘获稳定性进行了分析,着重研究了拓扑电荷和光束阶数对辐射力的影响。结果表明,随着拓扑电荷和光束阶数的增大,最大光强和辐射力随之减小;平顶光束可以俘获金瑞利粒子,俘获微粒的牢固性和俘获范围随着光束阶数增大而减小,而平顶涡旋光束的梯度力不能作为回复力,因此不能俘获。最后,还讨论了不同光强分布下,俘获金属瑞利粒子时复介电常数需满足的必要条件。更多还原

【Abstract】 Radiation forces and trapping stability of focused flat-topped beam and flat-topped vortex beam on metallic(i.e.gold) Rayleigh particle are analyzed,where the dependence of radiation forces on topological charge and beam order are stressed and illustrated by numerical examples.The results show that the maximum intensity and radiation forces(absolute value) decrease with increasing topological charge or beam order,and the trapping stiffness and range decrease with increasing the beam order of the flat-topped beam.The flat-topped beam can be used to trap gold Rayleigh particles at the geometrical focal plane,while the flat-topped vortex beam cannot trap the particles owing to the gradient force which could not act as restoring force.Finally,necessary conditions of complex dielectric constant for trapping metallic particles in different intensity profiles are discussed.更多还原