飞秒-Airy激光在大气湍流中的非直线传输特性及轨迹控制技术

The novel observation of femtosecond filamentation in air, it not only extremely expands the application range of laser in science and technology, but also brings new angle of view of nonlinear optics. The peculiarity of Airy beam can propagate along curve trajectory brings impact of classical understanding on the light propagating along straight line, this discovery causes extensive attention of scientists. It still on theoretical exploring ground for the formation of light bullet from filamentation and Airy beam, to deliver engineering application research in practice, it needs identify the linear and nonlinear effects, and also, the experimental confirmation of the feasibility and physical signification must be conducted firstly. It is an opportunity, as well as requirement of our research, we will take the first step in performing an investigate, by combining the filamentation characteristics of high-power femtosecond laser pulse propagating in air with the peculiarities of non-diffracting, self-bending of Airy beam, and taking the influence of atmospheric turbulence into account, the generation feasibility, the formation mechanism and propagation properties of light bullets in atmospheric turbulence will be studied and demonstrated. The scale relationships between the incident parameters and the formation position along the propagating path, the farthermost distance of light bullets should be obtained. The anti-disturbance capability of light bullets with different polarizations will be analyzed. To obtain the controlling technology parameters of arbitrary propagating trajectory of light bullets, pure phase function methods are utilized. The inherent dependence of propagating trajectory and atmospheric parameters can also be established therefore. it can also furnish valuable suggestions for engineering application of laser and the optimum design of laser propagation system.

飞秒激光大气成丝现象的发现，不仅极大的拓展了激光在科学与技术领域的应用范围，而且给人们对非线性光学的理解带来新的视角。Airy激光沿非直线传输特性的发现又给人们对光沿直线传输的传统认识带来新的冲击，这一特性引起了国内外科学家的广泛关注。将飞秒成丝与Airy激光非直线传输特性相结合形成光子弹，还处于理论探索阶段，开展应用型研究，还需要在弄清诸多线性与非线性特性等物理机理的基础上，实验验证光子弹产生与控制的可行性与科学性。本项目将结合飞秒成丝和艾里激光的无衍射、自弯曲等特性，考虑大气湍流的影响，分析光子弹产生的可行性，阐明光子弹在大气湍流中的形成机理和传输特性。建立发射系统参数与光子弹形成纵深位置和最远传输距离之间的定标关系；分析不同极化的光子弹对大气湍流的抗扰动能力。利用纯相位函数法获取光子弹沿任意轨迹传输的控制技术参数，建立传输轨迹与大气参数之间的依赖关系。为工程应用提供科学参考。

重点研究了飞秒-艾里光束在不同功率条件下的非线性传输特性，分析了非线性传输条件下艾里光束横向加速特性受到的影响程度，给出了在非线性条件下改变加速特性的技术方法。研究了大气湍流条件下，湍流强度、位置、湍流内尺度等参量对飞秒-艾里光束形成光子弹的可行性和稳定性影响程度。进一步分析了在高非线性条件下，圆对称分布的入射光束在突然自动聚焦传输过程中，形成等离子体通道的基本特性，分析了等离子体的产生对产生稳定三维时空光子弹的影响过程。重点研究了线偏振和圆偏振形式的飞秒艾里激光的传输特性，分析了它们在线性传输和非线性传输条件下的异同点。侧重研究了圆形艾里光束的时空传输特性和非线性焦点移动，探讨了克尔非线性聚焦和非线性多光子损耗对非线性传输稳定性的影响。