Influence of viscous force on the dynamic process of micro-sphere in optical tweezers  

作　　者：刘静 吴星宇 冯怡敏 郑冕 李志远 Jing Liu;Xingyu Wu;Yimin Feng;Mian Zheng;Zhiyuan Li(College of Computer Science,South-Central Minzu University,Wuhan 430074,China;China Ship Development and Design Center,Wuhan 430064,China;School of Physics and Optoelectronics,South China University of Technology,Guangzhou 510640,China)

机构地区：[1]College of Computer Science,South-Central Minzu University,Wuhan 430074,China [2]China Ship Development and Design Center,Wuhan 430064,China [3]School of Physics and Optoelectronics,South China University of Technology,Guangzhou 510640,China

出　　处：《Chinese Physics B》2023年第10期768-775,共8页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant No.11804399);the Special Funds for Basic Scientific Research at the Central University of South-Central University for Nationalities(Grant No.CZQ20018);Special Funds for Basic Scientific Research at Central Universities(Grant No.YZZ17005)。

摘　　要：With the advantages of noncontact,high accuracy,and high flexibility,optical tweezers hold huge potential for micro-manipulation and force measurement.However,the majority of previous research focused on the state of the motion of particles in the optical trap,but paid little attention to the early dynamic process between the initial state of the particles and the optical trap.Note that the viscous forces can greatly affect the motion of micro-spheres.In this paper,based on the equations of Newtonian mechanics,we investigate the dynamics of laser-trapped micro-spheres in the surrounding environment with different viscosity coefficients.Through the calculations,over time the particle trajectory clearly reveals the subtle details of the optical capture process,including acceleration,deceleration,turning,and reciprocating oscillation.The time to equilibrium mainly depends on the corresponding damping coefficient of the surrounding environment and the oscillation frequency of the optical tweezers.These studies are essential for understanding various mechanisms to engineer the mechanical motion behavior of molecules or microparticles in liquid or air.

关 键 词：optical tweezers viscous force equations of Newtonian mechanics Runge–Kutta method 

分 类 号：O43[机械工程—光学工程]