时域整形皮秒激光双脉冲烧蚀玻璃表面特性  

Picosecond Laser Ablation of Glass Surface by Dual⁃Pulse Temporal Shaping

作　　者：刘文凤 孙明营[1] 石逸群 郭亚晶[1] 徐英明 焦兆阳[1] 崔子健[1] 朱健强[1] Liu Wenfeng;Sun Mingying;Shi Yiqun;Guo Yajing;Xu Yingming;Jiao Zhaoyang;Cui Zijian;Zhu Jianqiang(National Laboratory on High Power Laser and Physics,Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 201800,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院上海光学精密机械研究所高功率激光物理重点实验室,上海201800 [2]中国科学院大学,北京100049

出　　处：《中国激光》2023年第12期81-91,共11页Chinese Journal of Lasers

基　　金：国家自然科学基金(61975218);中国科学院战略性先导科技专项(XDA25020202);中国科学院大科学计划培育专项(181231KYSB20170022);中国科学院青年创新促进会项目(2018282)。

摘　　要：基于亚纳秒间隔的皮秒激光双脉冲,研究了双脉冲时域整形对K9玻璃表面烧蚀特性的调控规律。当子脉冲间隔为667 ps时,不同形状双脉冲下玻璃表面的烧蚀形貌随激光通量增加的变化规律明显不同,而泵浦通量起着决定性作用。当泵浦通量低于阈值时,双脉冲烧蚀特性基本与单脉冲相似;当泵浦通量在阈值附近时,泵浦脉冲对玻璃表面的微纳米尺度的烧蚀会显著增强探测脉冲的烧蚀效应。当泵浦通量高于1.3倍阈值时,泵浦脉冲在玻璃与空气界面附近产生冲击波,探测脉冲被冲击波的高密度前沿界面反射和干涉,在中心烧蚀区域周围产生了圆环状烧蚀形貌,且圆环分布与探测通量密切相关。双脉冲烧蚀的内径尺寸与泵浦通量相关,而外径尺寸与双脉冲的形状、通量均相关。对比研究了子脉冲间隔为333 ps和667 ps时的等通量双脉冲烧蚀形貌,结果发现:低通量下较小的脉冲间隔可以增强烧蚀效应;高于烧蚀阈值的泵浦脉冲会影响探测脉冲的能量沉积;两种脉冲间隔下环状形貌的不同反映了泵浦脉冲产生的冲击波的传输特性不同。最后基于实验结果讨论了双脉冲序列时域整形进行表面烧蚀调控的物理机制。Objective In recent years,ultrashort pulsed laser material micromachining based on the burst mode has received extensive attention,and the burst mode is an effective method to improve the efficiency and quality of material removal.For higher processing efficiency,the subpulse repetition frequency is increased to GHz,which enables the precise regulation of both electron dynamics and thermal effects and thus the control and optimization of the ablation mechanism and effect.However,pulse train ablation involves complex physical processes and experimental phenomena.It is important to study the physical mechanisms of pulse train ablation.Research on laser micromachining of GHz pulse trains mainly focuses on femtosecond lasers;however,the ablation effect of picopulse trains is still less studied,although picosecond lasers are currently the most widely used in industry.Pico-and femto-pulses have significant ablation effect differences.Among them,dual-pulse(pump-probe)is the simplest form of the burst mode,which is the main method used to study the physical process of pulse train ablation.Therefore,the study of picosecond dual-pulse ablation is important to reveal the physical mechanism of picosecond burst ablation.In this study,we combined a dual-pulse train and temporal shaping to investigate the ablation process and mechanism of the K9 glass surface.Methods We proposed the temporal shaping of a dual-pulse train at the sub-nanosecond scale to study laser ablation on a glass surface.First,the time interval of the dual-pulse was fixed at 667 ps.The effects of single-and dual-pulses with various shapes on the laser ablation characteristics were studied by adjusting the energy ratio of the dual-pulse.The ablation morphology under different fluences was classified based on similarities with various dual-pulse shapes.Then,the distribution curve of the characteristic morphology with fluence was used to analyze the law of subpulse ablation.Second,we further reduced the time interval of the flatshaped dual-pulse to 333 ps and a

关 键 词：激光技术 激光烧蚀 皮秒激光 双脉冲 时域整形 

分 类 号：O437[机械工程—光学工程]