Höhm Sandra, Herzlieb Marcel, Rosenfeld Arkadi, Krüger Jörg, Bonse Jörn
Opt Express. 2015 Jan 12;23(1):61-71. doi: 10.1364/OE.23.000061.
Two-color double-fs-pulse experiments were performed on silicon wafers to study the temporally distributed energy deposition in the formation of laser-induced periodic surface structures (LIPSS). A Mach-Zehnder interferometer generated parallel or cross-polarized double-pulse sequences at 400 and 800 nm wavelength, with inter-pulse delays up to a few picoseconds between the sub-ablation 50-fs-pulses. Multiple two-color double-pulse sequences were collinearly focused by a spherical mirror to the sample. The resulting LIPSS characteristics (periods, areas) were analyzed by scanning electron microscopy. A wavelength-dependent plasmonic mechanism is proposed to explain the delay-dependence of the LIPSS. These two-color experiments extend previous single-color studies and prove the importance of the ultrafast energy deposition for LIPSS formation.
在硅片上进行了双色双飞秒脉冲实验，以研究激光诱导周期性表面结构（LIPSS）形成过程中的时间分布能量沉积。马赫-曾德尔干涉仪产生波长为400和800 nm的平行或交叉偏振双脉冲序列，在亚消融50飞秒脉冲之间的脉冲间延迟可达几皮秒。多个双色双脉冲序列通过球面镜共线聚焦到样品上。通过扫描电子显微镜分析所得的LIPSS特性（周期、面积）。提出了一种波长相关的等离子体机制来解释LIPSS的延迟依赖性。这些双色实验扩展了先前的单色研究，并证明了超快能量沉积对LIPSS形成的重要性。
