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arXiv · 1805.12240

A 3D DPG Maxwell Approach to Nonlinear Raman Gain in Fiber Laser Amplifiers

S. Nagaraj·J. Grosek·S. Petrides·L. Demkowicz·J. Mora
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Abstract

We propose a three dimensional Discontinuous Petrov-Galerkin Maxwell approach for modeling Raman gain in fiber laser amplifiers. In contrast with popular beam propagation models, we are interested in a truly full vectorial approach. We apply the ultraweak DPG formulation, which is known to carry desirable properties for high-frequency wave propagation problems, to the coupled Maxwell signal/pump system and use a nonlinear iterative scheme to account for the Raman gain. This paper also introduces a novel and practical full-vectorial formulation of the electric polarization term for Raman gain that emphasizes the fact that the computer modeler is only given a measured bulk Raman gain coefficient. Our results provide promising qualitative corroboration of the model and methodology used.

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S. Nagaraj, J. Grosek, S. Petrides, L. Demkowicz, J. Mora. 2018-05-30. A 3D DPG Maxwell Approach to Nonlinear Raman Gain in Fiber Laser Amplifiers. https://arxiv.org/abs/1805.12240

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