Ruiz de la Cruz A, Lahoz R, Siegel J, de la Fuente G F, Solis J
Opt Lett. 2014 Apr 15;39(8):2491-4. doi: 10.1364/OL.39.002491.
We report on the fabrication of laser-induced periodic surface structures in Cr films upon high repetition rate fs laser irradiation (up to 1 MHz, 500 fs, 1030 nm), employing beam scanning. Highly regular large-area (9 cm2) gratings with a relative diffraction efficiency of 42% can be produced within less than 6 min. The ripple period at moderate and high fluences is 0.9 μm, with a small period of 0.5 μm appearing at lower energies. The role of the irradiation parameters on the characteristics of the laser-induced periodic surface structures (LIPSS) is studied and discussed in the frame of the models presently used. We have identified the polarization vector orientation with respect to the scan direction as a key parameter for the fabrication of high-quality, large-area LIPSS, which, for perpendicular orientation, allows the coherent extension of the sub-wavelength structure over macroscopic distances. The processing strategy is robust in terms of broad parameter windows and applicable to other materials featuring LIPSS.
我们报道了在高重复频率飞秒激光辐照（高达1MHz，500fs，1030nm）下，采用光束扫描在Cr膜中制备激光诱导周期性表面结构的情况。在不到6分钟的时间内，可以制备出相对衍射效率为42%的高度规则的大面积（9平方厘米）光栅。在中等和高能量密度下，波纹周期为0.9μm，在较低能量下出现0.5μm的小周期。在目前使用的模型框架内，研究并讨论了辐照参数对激光诱导周期性表面结构（LIPSS）特性的影响。我们已经确定，相对于扫描方向的偏振矢量方向是制备高质量、大面积LIPSS的关键参数，对于垂直方向，它允许亚波长结构在宏观距离上相干扩展。该加工策略在宽参数窗口方面具有鲁棒性，并且适用于其他具有LIPSS的材料。
