Jiewei Guo 1,2Lu Sun 1,2Yuezheng Wang 1,2Jiayun Xue 1,2[ ... ]Weiwei Liu 1,2
Author Affiliations
Abstract
1 Institute of Modern Optics, Eye Institute, Nankai University, Tianjin 300350, China
2 Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Tianjin 300350, China
3 Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Tianjin 300350, China
The effects of turbulence intensity and turbulence region on the distribution of femtosecond laser filaments are experimentally elaborated. Through the ultrasonic signals emitted by the filaments, it is observed that increasing turbulence intensity and an expanding turbulence active region cause an increase in the start position of the filament and a decrease in filament length, which can be well explained by theoretical calculation. It is also observed that the random perturbation of the air refractive index caused by atmospheric turbulence expands the spot size of the filament. Additionally, when the turbulence refractive index structure constant reaches 8.37×10-12 m-2/3, multiple filaments are formed. Furthermore, the standard deviation of the transverse displacement of filament is found to be proportional to the square root of the turbulent structure constant under the experimental turbulence parameters in this paper. These results contribute to the study of femtosecond laser propagation mechanisms in complex atmospheric turbulence conditions.
femtosecond laser filamentation turbulence 
Chinese Optics Letters
2023, 21(11): 110004
薛嘉云 1,2齐鹏飞 1,2郭兰军 1,2张楠 1,2[ ... ]刘伟伟 1,2
作者单位
摘要
1 南开大学现代光学研究所,天津 300350
2 天津市微尺度光学信息技术科学重点实验室,天津 300350
3 天津市光电传感器与传感网络重点实验室,天津 300350
光丝内部的超高钳制光强可诱导大气中的原子、分子等发生隧道电离或多光子电离,并辐射指纹荧光谱。得益于其在复杂大气环境中能够远距离传输的特点,飞秒激光成丝在大气远程探测方面具有广阔的应用前景。光丝诱导物质荧光的空间分布特性与成丝过程中激光、等离子体等参数密切相关,对于理解光丝内物理过程及调控光丝、提升远程探测信噪比等具有重要意义。综述了光丝诱导荧光在侧向、背向及前向三个重要方位的空间分布的研究进展,详细讨论了基于侧向分布表征光丝内光强及等离子体分布的方法,以及实验条件对荧光空间分布的影响,并对放大自发辐射现象及前向、背向远场空间分布的研究进展进行了介绍。最后对飞秒激光成丝诱导荧光空间分布的研究趋势进行了展望。
非线性光学 激光光学 飞秒激光成丝 大气远程探测 nonlinear optics laser optics femtosecond laser filamentation remote atmosphere detection 
中国激光
2023, 50(7): 0708001
薛嘉云 1,2陶诗诗 1,2郭兰军 1,3,*张智 1,3[ ... ]刘伟伟 1,2
作者单位
摘要
1 南开大学 现代光学研究所,天津 300350
2 天津市微尺度光学信息技术科学重点实验室,天津 300350
3 天津市光电传感器与传感网络重点实验室,天津 300350
对高能量掺镱激光器进行腔外压缩,是获得高能量少数周期脉冲的重要方式。通过数值模拟研究了单脉冲能量为250 mJ,波长为1 030 nm的高能量掺镱激光器通过固体多薄片介质进行非线性脉冲压缩的过程,及介质周期、厚度对频谱展宽的影响。在优化频谱展宽条件的过程中发现,不超过介质损伤阈值的情况下,固体薄片组的周期和厚度对频谱展宽具有正向影响。通过选取合适的介质厚度及周期,激光频谱通过熔融石英介质进行展宽,最终输出的光谱带宽达229 nm,补偿色散后,激光脉冲由500 fs压缩至16.2 fs,压缩比达到30。研究结果为实现高能量激光脉冲的非线性压缩提供了理论参考。
脉冲压缩 非线性光谱展宽 自相位调制 色散补偿 飞秒激光 Pulse compression Nonlinear spectral broadening Self-phase modulation Dispersion compensation Femtosecond laser 
光子学报
2023, 52(1): 0114001
Author Affiliations
Abstract
1 Institute of Modern Optics, Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, Nankai University, Tianjin 300350, China
2 School of Physical Science and Technology, Tiangong University, Tianjin 300387, China
The spatial distribution of the forward-propagating amplified spontaneous emission (ASE) of nitrogen molecular ions during femtosecond laser filamentation in air is studied via numerical simulations. The results suggest that the divergence angle and signal intensity are extremely sensitive to the external focal length. Concurrently, we show that the optical Kerr effect plays a significant role in concentrating the directivity of ASE signals, particularly in cases of loose focusing. Furthermore, the simulations demonstrate that ASE signals are enhanced for a tight focus, although the corresponding filament length is shorter. The main physical mechanism underlying this process is the competition between the plasma defocusing and optical Kerr effects. The result is important for filamentation-based light detection and ranging applied to remote sensing.
air laser amplified spontaneous emission femtosecond laser filamentation 
Chinese Optics Letters
2021, 19(8): 081402
作者单位
摘要
1南开大学现代光学研究所天津市微尺度光学信息技术科学重点实验室, 天津 300350
超快激光成丝是高功率超快激光在透明光学介质中传输时出现的一种独特非线性光学现象,所产生长度远超共焦范围的离子体通道被称为光丝;同时伴随超连续谱产生、荧光辐射和受激放大、脉冲自压缩等丰富的光学效应,在大气遥感、超快激光技术、人工干预天气、激光超精细加工等方面具有广泛应用前景。本文对成丝现象研究的历史发展进行了简单介绍,包括实验技术、基本物理机制和调控方法的主要研究进展,并对成丝在大气远程应用、物理化学机制、强THz波产生等方面的研究所面临的挑战进行了展望。
激光光学 超快激光 非线性光学 激光成丝 超快激光现象 laser optics ultrafast laser nonlinear optics laser filamentation ultrafast phenomena 
中国激光
2020, 47(5): 0500003

关于本站 Cookie 的使用提示

中国光学期刊网使用基于 cookie 的技术来更好地为您提供各项服务,点击此处了解我们的隐私策略。 如您需继续使用本网站,请您授权我们使用本地 cookie 来保存部分信息。
全站搜索
您最值得信赖的光电行业旗舰网络服务平台!