飞秒激光诱导石墨表面周期性纳米结构

Nanoscale Period Surface Structure of Graphite Induced by Femtosecond Laser

介绍了使用近阈值飞秒激光(脉宽130fs,中心波长800nm)烧蚀高定向热解石墨(HOPG)的实验,研究了激光强度与烧蚀深度、激光强度与烧蚀面积之间的关系,计算得到石墨的烧蚀阈值为0.44J/cm2。使用SEM观察样品表面的烧蚀凹坑,发现两种不同的周期性纳米结构,其周期分别为400nm和100nm左右。通过改变脉冲数量、激光能量等参数,分析了各种结构的形成条件。

Experiment of femtosecond laser ablation of highly-ordered pyrolytic graphite is performed. Ablation depth and area are investigated as a function of incident energy. The calculated ablation threshold is 0.44 J/cm^2. Two different periodic nanostructures are obtained after laser ablation at a wavelength of 800 nm and a duration of 130 fs, including a low-spatial-frequency structure with period of about 400 nm and a high-spatial-frequency with period of about 100 nm. Formation conditions of the nanostructures are analyzed by changing the parameters such as laser energy and pulse number.