We investigate the impact of the spatial beam oscillations in a graded-index multimode fiber (MMF) upon the trapping and blue-shifting of dispersive pulses by a multimode soliton. We find that the dispersive pulses trapped by solitons can be controlled through adjusting the degree of compression of the spatial beam. This can provide an explanation for the enhanced blue spectral extension observed in the typical supercontinuum generation in graded-index MMFs. Besides, the spatial-temporal nonlinear effect may provide an additional degree of freedom for the spectrally tailored light generation and the ultrashort pulse generation with tunable wavelengths in the normal dispersion regime.

中文翻译：

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梯度折射率多模光纤中孤子捕获色散波的时空控制

我们研究了梯度折射率多模光纤（MMF）中空间束振荡对多模孤子的色散脉冲的捕获和蓝移的影响。我们发现，可以通过调节空间光束的压缩程度来控制由孤子捕获的色散脉冲。这可以为梯度指数MMF中典型超连续谱生成中观察到的增强的蓝色光谱扩展提供解释。此外，时空非线性效应可以为光谱定制的光产生和正常色散状态下具有可调波长的超短脉冲产生提供额外的自由度。