运用四元数分析椭球微粒所受的光阱力

发布时间：2018-01-25 03:02

本文关键词： 四元数光线追迹椭球微粒光阱力　出处：《物理学报》2017年04期 　论文类型：期刊论文

【摘要】：在光镊的射线模型中,追迹光线在界面的折射反射光是较基本的也是较复杂的问题.传统的几何光学法计算光线的方位,对于一些不规则的物体来说,存在一定的困难度.本文提出使用四元数简化空间光线追迹,从而可计算非球形颗粒的光阱力.以入射光线和界面法线的外积确定入射面的法线为旋转轴;根据折射定律确定由入射光线旋转到反射光线和折射光线的角度.将入射光线以四元数表示,根据四元数旋转,可获得反射光线和折射光线的空间矢量.根据光子的动量变化,求得光阱对微粒的作用力.本文以球差影响下的不同形变的椭球为计算示例,模拟了椭球在光阱下的动力学行为,结果表明椭球的横向和轴向俘获效率受到各方向变形系数的影响;球差增大降低了轴向的最大俘获效率,稳定俘获位置也随之朝负轴偏离中心更远;在固定球差作用下,最大轴向俘获效率与轴向变形系数相关,在特定的变形下轴向俘获效率变得较大.由此验证了四元数方法的正确性、实用性与普遍性.
[Abstract]:In the ray model of optical tweezers, the refraction and reflection of tracing light at the interface is a relatively basic and complex problem. The traditional geometric optics method is used to calculate the azimuth of light, for some irregular objects. In this paper, the quaternion is used to simplify the space ray tracing, so that the optical trap force of the non-spherical particles can be calculated. The normal line of the incident plane is determined as the axis of rotation by the external product of the incident light and the normal line of the interface. According to the law of refraction, the angle of rotation from incident light to reflected light and refraction light is determined. The incident light is expressed as quaternion and rotated according to quaternion. The space vector of reflected light and refraction light can be obtained. According to the change of photon momentum, the force of optical trap on particles can be obtained. In this paper, the ellipsoid with different deformation under the influence of spherical aberration is taken as an example. The dynamic behavior of the ellipsoid in the optical trap is simulated. The results show that the transverse and axial capture efficiency of the ellipsoid is affected by the deformation coefficient in each direction. With the increase of spherical aberration, the maximum capture efficiency is reduced, and the stable capture position is further away from the center of the negative axis. Under the action of fixed spherical aberration, the maximum axial capture efficiency is related to the axial deformation coefficient, and the axial capture efficiency becomes larger under specific deformation, which verifies the correctness, practicability and universality of the quaternion method.
【作者单位】：安徽医科大学生物医学工程系;
【基金】：国家自然科学基金青年基金项目(批准号:31400943) 安徽高校自然科学研究重点项目(批准号:KJ2016A361) 安徽医科大学博士科研资助基金(批准号:XJ201518)资助的课题~~
【分类号】：O435.1
【正文快照】： 长的光阱力,即使在颗粒尺寸与波长相近时,也能1引言取得与实验相近的结果,在光镊发展的30年内不断得到应用和推广.目前光镊广泛应用于单分子检测马达蛋在RO模型中,Ashkin[11]提出的射线追踪的白[1,2],DNA和RNA力学特性分析[3]、测量细胞模型可以很好地分析球形颗粒在光阱中的

【相似文献】