用菲涅耳波带片俘获两个Rayleigh粒子  

Trapping two Rayleigh Particles Using a Subwavelength Fresnel Zone Plate

作　　者：赵艳[1] 海福生[2] 张耀举[1] 

机构地区：[1]温州大学物理与电子信息工程学院,浙江温州325035 [2]河南大学药学院,河南开封475004

出　　处：《河南大学学报（自然科学版）》2014年第5期526-531,共6页Journal of Henan University:Natural Science

基　　金：国家自然科学基金项目(61377021;61078023);浙江省公益性技术应用研究项目(2010C31051)

摘　　要：提出了一个同时俘获两个Rayleigh粒子的光学俘获模型.用一束双环形拉盖尔高斯(LG10)径向偏振光入射到高数值孔径的亚波长菲涅耳波带片(SFZP)上,利用角谱理论计算波带片后的衍射场分布.结果显示,通过调节入射光的截断参数(β),在近场区和菲涅尔衍射区产生了两个绕光轴旋转对称的亮斑.两个亮斑均可以用来同时俘获Rayleigh粒子.最后讨论了俘获精度和俘获的稳定性.A model of optical trapping two high refractive index Rayleigh particles simultaneously is proposed. A double-ring-shaped Laguerre-Gaussian （LG10） radially polarized beam is incident on a subwavelength Fresnel zone plate （SFZP）. Based on the angular spectrum theory, the diffraction field distribution of the SFZP is calculated. Calculation results shown that, by changing the truncation parameter （β） of the incident beam, two cylindrically symmetric bright spots are generated in the near-field region and in Fresnel-diffraction region, respectively, which can be used to simultaneously trap two Rayleigh particles. The trapping accuracy and stability are also discussed in this paper.

关 键 词：光学俘获 菲涅耳波带片 径向偏振 截断参数 Rayleigh粒子 

分 类 号：O436.1[机械工程—光学工程]