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arXiv · 1905.02874

Simulation of Optical Fiber Amplifier Gain Using Equivalent Short Fibers

Dow Drake·Jay Gopalakrishnan·Tathagata Goswami·Jacob Grosek
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Abstract

Electromagnetic wave propagation in optical fiber amplifiers obeys Maxwell equations. Using coupled mode theory, the full Maxwell system within an optical fiber amplifier is reduced to a simpler model. The simpler model is made more efficient through a new scale model, referred to as an equivalent short fiber, which captures some of the essential characteristics of a longer fiber. The equivalent short fiber can be viewed as a fiber made using artificial (unphysical) material properties that in some sense compensates for its reduced length. The computations can be accelerated by a factor approximately equal to the ratio of the original length to the reduced length of the equivalent fiber. Computations using models of two commercially available fibers -- one doped with ytterbium, and the other with thulium -- show the practical utility of the concept. Extensive numerical studies are conducted to assess when the equivalent short fiber model is useful and when it is not.

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Dow Drake, Jay Gopalakrishnan, Tathagata Goswami, Jacob Grosek. 2019-05-04. Simulation of Optical Fiber Amplifier Gain Using Equivalent Short Fibers. https://doi.org/10.1016/j.cma.2019.112698

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