1 中国科学院上海光学精密机械研究所强场激光物理国家重点实验室, 上海 201800
2 上海师范大学物理系, 上海 200234
3 拉瓦尔大学光学、光子学和激光研究中心(COPL), 加拿大 魁北克 G1V 0A6
综述了飞秒激光人工影响天气的相关研究结果。从飞秒激光成丝产生的光氧化副产物、热沉积效应、气溶胶形成和水凝结及沉降过程等4个方面展开,综述了飞秒激光在诱导水凝结及降水、人工引雷等领域的研究进展。提出了飞秒激光人工影响环境大气的初步物理图像,并综述了该技术未来应用于人工影响天气所面临的问题,探讨了可能的解决方案。
非线性光学 飞秒光丝 光化学反应 气溶胶 水凝结
1 中国科学院上海光学精密机械研究所强场激光物理国家重点实验室, 上海 201800
2 中国科学院大学, 北京 100049
3 上海交通大学聚变科学与应用协同创新中心, 上海 200240
4 上海师范大学物理系, 上海 200234
5 中国科学院大气物理研究所中层大气和全球环境探测重点开放实验室, 北京 100029
6 拉瓦尔大学光学、光子学和激光研究中心, 加拿大 魁北克市 G1V 0A6
在室温条件下的小型云室中,研究了不同参数对飞秒激光诱导较大尺寸气溶胶生成的影响。实验结果表明,在亚饱和条件下,随着环境相对湿度的提高,不同尺寸气溶胶的数密度增大,尺寸分布以0.3~0.5 μm为主;当环境相对湿度达到近饱和条件时,较大尺寸(直径D≥0.7 μm)气溶胶的数密度显著增大,1.0~2.0 μm气溶胶与0.3~0.5 μm气溶胶的数密度可相比拟。此时,通过延长激光照射时间或者缩紧激光聚焦条件,不同尺寸气溶胶的数密度可同等程度地增大,尺寸分布规律基本不变。理论分析结果表明,环境相对湿度条件是制约飞秒激光诱导较大尺寸气溶胶生成的关键因素。
超快光学 非线性光学 飞秒光丝 气溶胶 光化学反应
Author Affiliations
Abstract
1 State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 MOE Key Laboratory of Advanced Micro-structured Materials, Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
3 IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, China
4 Center for Optics, Photonics and Laser (COPL), Laval University, Quebec City, Quebec G1V 0A6, Canada
Sub-picosecond chirped laser pulse-induced airflow and water condensation were investigated in a cloud chamber. The results indicate that the positively chirped sub-picosecond laser pulses generate a more uniform intensity distribution inside the plasma column, leading to a weaker airflow and an elliptic-shaped snow pile. The negatively chirped sub-picosecond laser pulses generate a spark-like intensity distribution inside the plasma column, which produces a wider range of airflow and a round snow pile. The amount of snow weight and the concentration of NO3 are found to be dependent on the intensity distribution inside the plasma column. The visibly stronger plasma column generates much more snow and a higher concentration of NO3 . These experimental results provide a reference for sub-picosecond laser-induced water condensation in realistic atmospheric conditions.
140.3450 Laser-induced chemistry 320.7110 Ultrafast nonlinear optics 010.3920 Meteorology Chinese Optics Letters
2018, 16(6): 061403
Author Affiliations
Abstract
1 MOE Key Laboratory of Advanced Micro-structured Materials, Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
2 State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
3 IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, China
4 Center for Optics, Photonics and Laser (COPL), Laval University, Quebec City, Quebec G1V 0A6, Canada
We report on the experimental observation of the airflow motion induced by an 800 nm, 1 kHz femtosecond filament in a cloud chamber filled with air and helium. It is found that vortex pairs with opposite rotation directions always form both below and above the filaments. We do not observe that the vortices clearly formed above the filament in air just because of the formation of smaller particles with weaker Mie scattering. Simulations of the airflow motion in helium are conducted by using the laser filament as a heat source, and the simulated pattern of vortices and airflow velocity agree well with the experimental results.
140.0140 Lasers and laser optics 190.0190 Nonlinear optics 320.0320 Ultrafast optics Chinese Optics Letters
2016, 14(3): 031401
Author Affiliations
Abstract
State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
Filamentation-induced water condensation and snow formation are investigated using laser pulses with different chirps and pulse widths. Chirped pulses result in the laser filamentation with different spatial lengths and intensities, which has a great impact on airflow motion and snow formation. The experiments show that snow formation mainly relates to the filament intensity distribution. Negative chirped pulses produce a greater amount of snow because of higher intensity inside the filaments as compared with the positive chirped pulses.
320.0320 Ultrafast optics 190.0190 Nonlinear optics 140.0140 Lasers and laser optics Chinese Optics Letters
2015, 13(3): 033201
