论文标题
笑容多模光纤中的非线性光束自我成像和自我关注动力学：理论和实验
Nonlinear beam self-imaging and self-focusing dynamics in a GRIN multimode optical fiber: theory and experiments
论文作者
论文摘要
对于许多应用，非线性分级多模纤维中的光束自我成像引起了人们的关注，例如通过多模层干扰在光纤激光器中实现快速的饱和吸收器机制。我们获得了一个精确的解决方案，用于通过分级索引多模纤维携带的激光束的一阶和二阶矩的非线性演变，预测空间自我导象时间不会随幂而变化。而光束宽度的振荡幅度依赖于功率。我们已经通过飞秒激光脉冲传播在异常和正常的分散体中，通过飞秒激光脉冲的传播进行了实验研究。通过可见的荧光发射和谐波产生的光散射从纤维芯中散射，使我们可以直接确认自我成像时期是随着功率而不变的。还强调了在自我关注的行动下的自我成像过程的空间转移和分裂。
Beam self-imaging in nonlinear graded-index multimode optical fibers is of interest for many applications, such as implementing a fast saturable absorber mechanism in fiber lasers via multimode interference. We obtain an exact solution for the nonlinear evolution of first and second order moments of a laser beam carried by a graded-index multimode fiber, predicting that the spatial self-imaging period does not vary with power. Whereas the amplitude of the oscillation of the beam width is power-dependent. We have experimentally studied the longitudinal evolution of beam self-imaging by means of femtosecond laser pulse propagation in both the anomalous and the normal dispersion regime of a standard telecom graded-index multimode optical fiber. Light scattering out of the fiber core via visible fluorescence emission and harmonic wave generation permits us to directly confirm that the self-imaging period is invariant with power. Spatial shift and splitting of the self-imaging process under the action of self-focusing are also emphasized.
