基于微光纤尖端激光脉冲推进微球  

Microspheres Propelled by Laser Pulses Based on Microfiber Tip

作　　者：邢继伟 孙文慧 刘雪连 刘艳芬[1] 刘晓华[1] 刘晓军[1] 郝斌政[1] 李建军 罗旺[1] 李奇楠[1] 于海超 Xing Jiwei;Sun Wenhui;Liu Xuelian;Liu Yanfen;Liu Xiaohua;Liu Xiaojun;Hao Binzheng;Li Jianjun;Luo Wang;Li Qinan;Yu Haichao(Department of Physics,College of Science,Qiqihar University,Qiqihar 161006,Heilongjiang,China)

机构地区：[1]齐齐哈尔大学理学院物理系,黑龙江齐齐哈尔161006

出　　处：《光学学报》2024年第9期142-148,共7页Acta Optica Sinica

基　　金：国家自然科学基金(61775044);黑龙江省高校基本科研业务费(135509218,145109309,145209133);博士研究启动基金(340279)。

摘　　要：本文研究了基于锥形光纤结构的激光推进微球,并基于该结构探究推进机制、微球运动的影响因素。光纤尖端出射的激光能量超过空气的电离阈值而产生等离子体,随后等离子体膨胀形成的冲击波通过反冲作用驱动微球。结果表明,微球的推进冲击波弹射机制发挥了主导作用。研究了激光能量和微球直径对微球运动的影响,发现微球的运动距离依赖于光纤尖端出射激光能量和微球尺寸。此外,分析了光纤尖端尺寸对激光能量、能量密度的影响,揭示出尖端出射激光能量呈非线性增加,能量密度表现出相反的变化趋势。该研究可能为在微米水平上对胶体和生物物质的指令操作提供更多的理论支撑。Objective The interaction between laser pulses and materials has been extensively studied in recent decades as a common physical mechanism,such as laser propulsion(LP)and laser-induced breakdown spectroscopy.LP has gained widespread attention due to its inherent advantages of reducing launch costs and increasing payload.With the development of LP,the research field has gradually transitioned from macroscopic to microscopic fields.However,during the propulsion process,the direct irradiation of high-energy laser pulses on particles can cause permanent damage to the particle surface,and the large laser spot size can lead to deviations in the particle’s trajectory.Therefore,a device that can control the spot diameter and reduce surface damage to particles needs to be proposed.In this work,we propose LP based on a tapered fiber to realize the propulsion of microscale microspheres and analyze the mechanism of LP based on the motion of microspheres.We study the effects of laser energy and microsphere size on the distance of the microsphere.In addition,we analyze the influence of laser energy emitted from the fiber tip on the fiber tip size and discuss the relationship between laser energy density and fiber tip diameter,revealing the nonlinear increase in laser energy and the decrease in scattering loss as the fiber diameter increases.Our research may provide further support for the precise manipulation of colloids and biomaterials at the micrometer level.Methods 1)Experimental setup for LP.A tapered fiber structure is prepared through flame heating.A Nd∶YAG laser is coupled into the fiber using a 40×objective lens and emitted from the fiber tip.The tip and microspheres are placed on three-dimensional translation stages.By the combination of vertical CCD1 and horizontal CCD2,the driven microspheres can be flexibly and precisely controlled.The dynamics of the microspheres are captured by the CCD1 camera.After the propulsion experiment is completed,the laser energy emitted from the fiber tip is measured by an energy m

关 键 词：激光 锥形光纤 等离子体 脉冲 冲击波 

分 类 号：O439[机械工程—光学工程]