PCCL光束对瑞利粒子作用力的理论研究  

Theoretical study on the force of PCCL beam on Rayleigh particles

作　　者：谢陈 屈军[1] XIE Chen;QU Jun(School of Physics and Electronic Information,Anhui Normal University,Wuhu 241002,China)

机构地区：[1]安徽师范大学物理与电子信息学院,芜湖241002

出　　处：《激光技术》2024年第5期698-704,共7页Laser Technology

基　　金：国家自然科学基金资助项目(12074005)。

摘　　要：为了探究部分相干月牙形光束(PCCL)对瑞利粒子的捕获特性,采用广义惠更斯-菲涅耳原理推导了PCCL光束经过ABCD光学系统传输后的交叉谱密度及对瑞利粒子作用力的表达式,对聚焦PCCL光束在焦平面的归一化光强和对瑞利粒子作用力的分布情况进行了软件模拟和理论分析,得到了聚焦PCCL光束的光强和捕获力随光束参量以及焦距变化的规律。结果表明,选取光束阶数n=3、初始腰宽w_(0)=0.1 mm、相干长度d_(0)=6 mm时,经焦距f=12 mm的透镜聚焦后的PCCL光束对高、低折射率粒子均能实现捕获;由于PCCL光束在焦平面处呈现离轴光强分布,峰值光强不在坐标原点,通过调节光束阶数、初始腰宽、相干长度和焦距,可实现对聚焦PCCL光强及瑞利粒子作用力的调控,从而实现聚焦PCCL光束对不同位置处瑞利粒子的灵活捕获。该研究结果为实际聚焦PCCL光束稳定捕获微粒提供了理论依据。To investigate the capture characteristics of Rayleigh particles by partially coherent crescent like beam(PCCL).The generalized Huygens Fresnel principle was adopted to derive the expression of the cross spectral density and the force on Rayleigh particles of PCCL beams transmitted through an ABCD optical system.Software simulation and theoretical analysis were conducted on the normalized intensity and force distribution on Rayleigh particles of a focused PCCL beam in the focal plane,and the patterns of the intensity and capture force of the focused PCCL beam changing with the beam parameters and focal length were obtained.The results show that when the beam order n=3,the initial waist width w_(0)=0.1 mm,and the coherence length d_(0)=6 mm,the PCCL beam focused by the lens with a focal length of f=12 mm,both high and low refractive index particles can be captured.Since the PCCL beam presents an off-axis light intensity distribution in the focal plane,and the peak light intensity is not at the coordinate origin,the focused PCCL light intensity and the force of Rayleigh particles can be controlled by adjusting the beam order,initial waist width,coherence length and focal length,so as to realize the flexible capture of Rayleigh particles at different positions by focusing the PCCL beam.The results of this study provide a theoretical basis for the stable capture of particles by focusing PCCL beams.

关 键 词：激光光学 聚焦 捕获 惠更斯-菲涅耳原理 部分相干月牙形光束 

分 类 号：O439[机械工程—光学工程]