He Weitao, Dai Jianan, Ma Qichang, Luo Aiping, Hong Weiyi
Opt Express. 2021 Mar 29;29(7):11353-11360. doi: 10.1364/OE.422667.
In this paper, we investigated the geometric parametric instability (GPI) in graded-index multimode fibers through the multimode generalized nonlinear Schrödinger equation. Our results clearly and intuitively indicate that the generations of GPI sidebands are nearly synchronous in the spectrums of all modes, and the shapes of these spectrums are nearly the same. The numerical results show that the energies of the GPI sidebands come from the pump sideband, and these sidebands are carried by similar spatial beam profiles due to the similar modal components. We also found that the large modal dispersion has an influence for the symmetry of these GPI sidebands.
在本文中，我们通过多模广义非线性薛定谔方程研究了渐变折射率多模光纤中的几何参数不稳定性（GPI）。我们的结果清晰直观地表明，在所有模式的频谱中，GPI边带的产生几乎是同步的，并且这些频谱的形状几乎相同。数值结果表明，GPI边带的能量来自泵浦边带，并且由于相似的模式成分，这些边带由相似的空间光束分布承载。我们还发现，大的模式色散对这些GPI边带的对称性有影响。
