School of Physics and Electronic Engineering, Xuzhou Normal University, Xuzhou 221116, China.
Opt Lett. 2011 Jun 15;36(12):2336-8. doi: 10.1364/OL.36.002336.
We numerically investigate the femtosecond filamentation dynamics in argon by considering the higher-order nonlinearities measured by a recent experiment. Our result indicates that, instead of plasma, these higher-order nonlinearities can provide main defocusing effect as shown by a recent theoretical work. However, when the higher-order nonlinearity is so strong to provide a main defocusing effect, some phenomena inconsistent with previous experiments such as pulse splitting and pulse self-compression can appear. Therefore, we infer that the values of higher-order nonlinear coefficients are overestimated, and the plasma should be the defocusing mechanism at least in the argon filament.
我们通过考虑最近实验测量的高阶非线性来数值研究氩气中的飞秒细丝形成动力学。我们的结果表明，与等离子体不同，这些高阶非线性可以提供主要的散焦效应，就像最近的一项理论工作所表明的那样。然而，当高阶非线性强到足以提供主要的散焦效应时，就会出现一些与以前的实验不一致的现象，如脉冲分裂和脉冲自压缩。因此，我们推断高阶非线性系数的值被高估了，在氩气细丝中，等离子体应该是散焦机制。
