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arXiv · 2610.41575

Phase transition dynamics of Abelian-Higgs vortices in the oscillating axion background

Naoya Kitajima·Shota Nakagawa
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Abstract

We investigate the effect of an oscillating axion background on thermally induced vortex-antivortex production in the Abelian-Higgs model. Through its coupling to the gauge field, the axion sources an electromagnetic response in the presence of vortex magnetic flux, modifying the dynamics of the vortices. We study this system using Langevin lattice simulations with dissipation and stochastic noise. It is shown that the phase transition dynamics of Abelian-Higgs vortices, namely the pair creation of vortex and antivortex under thermal fluctuations, can be significantly modified in the oscillating axion background. We find that the axion background shifts the rapid increase in the vortex density to lower temperature. In particular, this transition temperature becomes smaller as the oscillation frequency of the axion increases. The temperature dependence of the correlation length is also modified. These features provide a new experimental approach for the axion dark matter using superconducting devices.

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Naoya Kitajima, Shota Nakagawa. 2026-10-30. Phase transition dynamics of Abelian-Higgs vortices in the oscillating axion background. https://arxiv.org/abs/2610.41575

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