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arXiv · 2610.23761

Type 1.5 vortex bags in single component Ginzburg-Landau models with higher order potentials

Martin Speight·Thomas Winyard
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Abstract

We demonstrate the existence of type 1.5 like superconductivity in a single component Ginzburg-Landau model with a higher order potential. The model exhibits two competing superconducting Meissner states (MS), each of which has its own pair of length scales (coherence length and penetration depth). The solutions take the form of bags that contain vortices of one vacuum inside the other. This gives rise to four different types of vortex interaction, where one set of length scales determines vortex interactions inside the bags and the other set between the bags. Hence, within the bag the vortices can repel or attract and the bags themselves can repel or attract depending on the hierarchy of four length scales. When vortices repel within the bag, solutions act similarly to those in type 1.5 multicomponent superconductors, but in a single component system.

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Martin Speight, Thomas Winyard. 2026-10-16. Type 1.5 vortex bags in single component Ginzburg-Landau models with higher order potentials. https://arxiv.org/abs/2610.23761

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