T矩阵在光阱分析中的应用

光镊技术被广泛应用于许多生物领域。光镊本身结构简单，用单光束就可以捕获单个粒子，但对光阱力的精确计算却存在一定的难度。可以用一些近似的方法如几何光学或瑞利假设分析光阱力，但这些方法仅能在特定限制条件下适用。文中把电磁散射理论作为一种通用的方法来解决光阱力的计算问题。论述了如何使用T矩阵方法进行光阱力计算。计算结果为实验系统参量的选择提供了理论依据。

Application of T-matrix method in the analysis of optical trapping

The optical tweezers is widely used in many biological applications.Despite the apparent simplicity of a laser trap,a single particle is trapped with a single beam,exact calculation of the optical forces on particles is very difficult.Calculations can be performed by using some approximate methods such as Ray-Optics and Raleigh hypothesis,but these are only applicable within their ranges of validity.We can obtain a general theory for laser trapping by applying the electromagnetic scattering theory.In this paper, we describe how the T-matrix approach can be used to computer optical trapping force.According to the simulation results,we can easily choose parameters of the trapping system.