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arXiv · 2602.07416

Optical beam propagation inside a graded-index fiber with saturable nonlinearity

Tiyas Das·Anuj P. Lara·Samudra Roy·Govind P. Agrawal
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Abstract

We study theoretically the spatial evolution of optical beams inside a graded-index fiber exhibiting saturable nonlinearity. Utilizing an approach based on the variational principle, we identify the existence of bistable spatial solitons inside such a nonlinear medium, whose stability, analyzed through a linear stability analysis, is due to the saturating nature of the nonlinearity. Spatial solitons adhere to a specific amplitude-width relationship. Any deviation from this relationship leads to oscillating-type solutions with a period that increases with saturation level of the nonlinearity. Theoretically calculated values of this period agree well with numerical findings.

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Tiyas Das, Anuj P. Lara, Samudra Roy, Govind P. Agrawal. 2026-02-07. Optical beam propagation inside a graded-index fiber with saturable nonlinearity. https://arxiv.org/abs/2602.07416

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