单光束光镊光阱力分析

Analysis for Optical Trapping Force in Single Beam Optical Tweezers

在几何光学近似下,利用光线追踪法分析了激光微束对微粒的作用力,数值计算中考虑了激光微束的具体结构对光阱力的影响.分析表明:相对折射率和激光束腰对光阱力有重要影响,激光波长和微粒大小对光阱力也有一定影响.

By means of single beam tracing method, the force of micro-beam exerting to microscopic particles is analyzed in the condition of geometrical optics approximation. The effects of laser micro-beam on optical trapping force are introduced. Numerical results show that not only the relative refraction index has an important effect on optical trapping force, but also the optical waist has one, too. Furthermore, the wavelength of laser and the size of microscopic particles have a lesser effect on optical trapping force.