超短激光照射下颗粒的散射效应

对两个纳米颗粒受超短激光照射时表面吸收光强的分布情况进行了研究。基于米散射理论和蒙特卡罗方法建立程序来模拟和追踪光子的运动轨迹,米散射理论主要用于确定光子的散射方向,运用兰贝特定律和解析解对模拟结果进行验证。通过对比材料为金和黑体时双颗粒的光强分布发现,颗粒的散射和激光照射宽度的增加会使颗粒相邻处的光强增大,颗粒底部的光强主要取决于颗粒的反照率大小以及散射光强的分布情况。

Scattering effect of particles irradiated by ultrashort laser

The light intensity distribution of two nanoparticles irradiated by ultrashort laser is studied. A procedure based on Mie scattering theory and Monte Carlo method is built to simulate and trace the trajectories of photons. Mie scattering theory is mainly used to determine the scattering directions of photons. Through comparing the distribution function of gold particle and blackbody, the scattering between two particles and increasing of laser irradiating width will enhance the light intensity of particles where they are adjacent to each other. The intensity at the bottom of the particle is mainly decided by the albedo and distribution of scattering light.