陈柏桦1， 刘冬梅1,2， 邱 健1,2， 彭 力1,2， 骆开庆1,2， 韩 鹏1,2
（1. 华南师范大学 物理与电信工程学院； 广东省光电检测仪器工程技术研究中心, 广东 广州 510006;2. 华南师大(清远)科技创新研究院, 广东 清远 511517）
DOI:10.13732/j.issn.1008-5548.2021.03.009
收稿日期： 2020-10-20，修回日期：2021-02-04，在线出版时间：2021-04-20。
基金项目：国家自然科学基金项目，编号：61975058；广东省自然科学基金面上项目，编号：2019A1515011401；广东省科技计划项目，编号：2019B090905005。
第一作者简介：陈柏桦(1992—)，男，硕士研究生，研究方向为光电技术与系统。E-mail: 1453501039@qq.com。
通信作者简介：
韩鹏(1976—)，男，博士，教授，博士生导师，研究方向为光电技术与系统。E-mail: hanp@scnu.edu.cn。
刘冬梅(1981—)，女，博士，副教授，硕士生导师，研究方向为光电技术与系统。E-mail: dmliu@scnu.edu.cn。
摘要：基于差分动态显微技术，实验研究偏振光对颗粒布朗运动扩散系数的影响。实验结果表明，在弱聚焦条件下，布朗粒子在激光照射下的扩散系数比仅在白光照射下的扩散系数要小;在相同激光功率时，圆偏振光照射下颗粒扩散系数比线偏振光时的要小;随着入射激光功率的增大，线偏振光照射下的扩散系数表现出振荡的现象，而圆偏振光入射时，布朗运动扩散系数随功率的增大而减小。
关键词：扩散系数；布朗运动；偏振光；差分动态显微术
Abstract：Based on the differential dynamic microscopy technology,the experiment studies the effect of polarization on diffusion coefficient of Brownian particles in a weak focused laser. The results show that the diffusion coefficient of Brownian particles illuminating with the laser is smaller than that only with white light. Compared with the linearly polarized light,the diffusion coefficient is smaller than that under the circularly polarized light at the same input light power. The diffusion coefficient of Brownian motion fluctuates with the increase of input light power in the linearly polarized light,while the diffusion coefficient decreases with the increase of laser power under circularly polarized light.
Keywords：diffusion coefficient; Brownian motion; polarized light; differential dynamic microscopy
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