中文摘要：

超快强场激光在大气等光学介质中传输时会受到克尔自聚焦效应和等离子体散焦效应的动态调制,产生一种独特的非线性光学现象——激光成丝,在大气传感、太赫兹光谱产生、天气控制等研究领域具有重要的应用前景.针对超快强场激光在高温燃烧场成丝燃烧诊断应用,介绍了超快强场激光在燃烧场中成丝动力学过程以及传输成丝特性,综述了强场超快激光成丝诱导非线性光谱的机理及其在高温燃烧场诊断应用中的研究现状和进展,并探讨了当前强场超快激光成丝在该领域所面临的挑战和应用前景.

英文摘要：

The propagation of ultrafast strong laser in optical media such as ambient air can induce a dynamical balance between Kerr self-focusing and defocusing of plasma,resulting in a unique nonlinear phenomenon—laser filamentation,which have shown promising applications in areas such as atmospheric sensing,THz generation,and weather control.In this article,we present an overview of ultrafast strong laser filamentation in combustion fields and its potential application in combustion diagnostics,which is of particular significance in rationalizing the physical and chemical nature of combustion systems such as auto engines for efficient combustion of fuels with low-pollution products.We first introduce the dynamical processes and propagation properties of ultrafast strong laser filamentation in combustion fields,in which the determination of the two fundamental physical parameters,critical power and clamping intensity,for femtosecond laser filamentation in combustion flames is presented.Although these values in combustion flames are found to be smaller than in air,the intensity clamped in flame filaments are enough to induce multiple photon excitation and ionization of combustion intermediates such as CN,C_2 and CH free radicals,and atomic C and H to fluoresce.The fluorescence signals are sensitive to the position of interaction of the filament with the flame that indeed reflects the concentration distributions of the species to be sensed.We then present the underlying mechanisms of ultrafast strong laser filamentation induced nonlinear spectroscopy,in which the femtosecond filament-induced flame fluorescence emissions are found to mainly originate from the interaction of femtosecond laser pulses with the combustion intermediates existing in the combustion environment,but not from the fragmentation of parent fuel molecules.In particular,due to the high nonlinear properties of femtosecond laser filamentation in combustion flames,filamentinduced nonlinear flame fluorescence technique could be applied for simultaneous iden