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arXiv · 1310.4229

Constructing a class of topological solitons in magnetohydrodynamics

Amy Thompson·Joe Swearngin·Alexander Wickes·Dirk Bouwmeester
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Abstract

We present a class of topological plasma configurations characterized by their toroidal and poloidal winding numbers, $n_t$ and $n_p$ respectively. The special case of $n_t=1$ and $n_p=1$ corresponds to the Kamchatnov-Hopf soliton, a magnetic field configuration everywhere tangent to the fibers of a Hopf fibration so that the field lines are circular, linked exactly once, and form the surfaces of nested tori. We show that for $n_t \in \mathbb{Z}^+$ and $n_p=1$ these configurations represent stable, localized solutions to the magnetohydrodynamic equations for an ideal incompressible fluid with infinite conductivity. Furthermore, we extend our stability analysis by considering a plasma with finite conductivity and estimate the soliton lifetime in such a medium as a function of the toroidal winding number.

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Amy Thompson, Joe Swearngin, Alexander Wickes, Dirk Bouwmeester. 2014-04-26. Constructing a class of topological solitons in magnetohydrodynamics. https://doi.org/10.1103/physreve.89.043104

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