Propagation characteristics of radially shifted Gaussian beams and their radiation forces on Rayleigh particles
Propagation characteristics of radially shifted Gaussian beams and their radiation forces on Rayleigh particles
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DOI：
10.1016/j.optcom.2018.05.038
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发表时间：
2018-11
影响因子：
2.4
通讯作者：
Yunfeng Jiang;Shuofeng Zhao;Wenlei Yu;Xiuwei Zhu;Xin Zhang
中科院分区：
文献类型：
--
作者：
Yunfeng Jiang;Shuofeng Zhao;Wenlei Yu;Xiuwei Zhu;Xin Zhang
提出了一种新的严格高斯形暗空心光束（DHB），称为径向位移高斯光束（RSGB）。与以往的近似高斯形DHB[即空心高斯束（HGB）和空心辛高斯束（HsGB）]相比，使用RSGB设计任何特殊尺寸的DHB要方便得多。详细研究了RSGB的传输特性，特别是其自聚焦特性，并与HGB和HsGB在相同条件下的传输特性进行了比较。发现RSGB的空心区可以保持较长的距离；其自动对焦性能更强。本文还首次得到了高斯型DHB的焦点位置解析表达式。分析了两种瑞利粒子对光束的辐射力。数值结果表明，RSGB在二维光学显微操作中也比以往的高斯形DHB具有优势。对于低指数粒子，RSGB可以捕获更远的距离；对于高指数粒子，RSGB能在焦点处产生较大的俘获力。
A new kind of strictly Gaussian-shaped dark hollow beam (DHB), called radially shifted Gaussian beam (RSGB), is proposed in this paper. Compared with previous approximately Gaussian-shaped DHB [i.e., Hollow Gaussian beam (HGB) and hollow sinh-Gaussian beam (HsGB)], it is much more convenient to design any special sized DHB by using RSGB. The propagation characteristics of RSGB, especially its autofocusing property, are investigated in detail and compared with that of HGB and HsGB under the same condition. It is found that the hollow region of RSGB can remain for a longer distance; and its autofocusing property is much stronger. An analytical expression for the focal position is also obtained for Gaussian-shaped DHB for the first time. Radiation forces of these beams exerted on two kinds of Rayleigh particle are analyzed. Numerical results show that RSGB also has advantages over previous Gaussian-shaped DHB in two-dimensional optical micromanipulation. For the low-index particle, RSGB can trap it for a longer distance; for the high-index particle, RSGB can produce a larger trapping force at the focal point.