College of Optical Sciences, University of Arizona, Tucson, Arizona 85721, USA.
Opt Lett. 2010 Nov 1;35(21):3685-7. doi: 10.1364/OL.35.003685.
A recent experiment probing the electronic nonlinearity in the femtosecond filament indicated that the optical Kerr effect not only saturates but even changes its sign at high intensities and thus switches from self-focusing to a strongly defocusing regime. Here we examine, through simulations and experiment, some implications of such a behavior. We perform comparative simulations based on the standard model on one hand and on a model implementing the intensity-dependent Kerr effect on the other. Comparison with an experiment provides a strong indication that of these two Kerr-effect models the standard model is better in capturing the observed length of the filament. However, neither of the models can reproduce length and filament radius. Possible implications are discussed.
最近一项探测飞秒光丝中电子非线性的实验表明，在高强度下，光克尔效应不仅饱和，甚至其符号发生反转，从而从自聚焦切换到强烈的散焦状态。在这里，我们通过模拟和实验研究了这种行为的一些含义。我们一方面基于标准模型，另一方面基于实现强度相关克尔效应的模型进行了比较模拟。与实验的比较强烈表明，在这两个克尔效应模型中，标准模型更能捕捉到观察到的光丝长度。然而，这两个模型都无法再现光丝的长度和半径。讨论了可能的影响。
