Nivas Jijil J J, Shutong He, Anoop K K, Rubano A, Fittipaldi R, Vecchione A, Paparo D, Marrucci L, Bruzzese R, Amoruso S
Opt Lett. 2015 Oct 15;40(20):4611-4. doi: 10.1364/OL.40.004611.
We investigate laser ablation of crystalline silicon induced by a femtosecond optical vortex beam, addressing how beam properties can be obtained by analyzing the ablation crater. The morphology of the surface structures formed in the annular crater surface allows direct visualization of the beam polarization, while analysis of the crater size provides beam spot parameters. We also determine the diverse threshold fluences for the formation of various complex microstructures generated within the annular laser spot on the silicon sample. Our analysis indicates an incubation behavior of the threshold fluence as a function of the number of laser pulses, independent of the optical vortex polarization, in weak focusing conditions.
我们研究了飞秒光学涡旋光束诱导的晶体硅激光烧蚀，探讨了如何通过分析烧蚀坑来获得光束特性。环形坑表面形成的表面结构形态可直接观察光束偏振，而对坑尺寸的分析则可提供束斑参数。我们还确定了硅样品上环形激光光斑内产生各种复杂微结构的不同阈值能量密度。我们的分析表明，在弱聚焦条件下，阈值能量密度存在与光学涡旋偏振无关的、随激光脉冲数变化的孕育行为。
