Topological phase transitions in the gauged BPS baby Skyrme model

TL;DR

This paper investigates phase transitions in the gauged BPS baby Skyrme model, showing how external pressure and magnetic fields induce a transition from a non-solitonic to a solitonic phase, with implications for topological matter.

Contribution

It introduces the analysis of phase transitions in the gauged BPS baby Skyrme model driven by external parameters, revealing a critical line and the equation of state for soliton matter.

Findings

Phase transition from non-solitonic to solitonic phase with increasing pressure or magnetic field.

Identification of a critical line in the pressure-magnetic field parameter space.

Derivation of the equation of state for baby skyrmion matter at zero temperature.

Abstract

We demonstrate that the gauged BPS baby Skyrme model with a double vacuum potential allows for phase transitions from a non-solitonic to a solitonic phase, where the latter corresponds to a ferromagnetic liquid. Such a transition can be generated by increasing the external pressure $P$ or by turning on an external magnetic field $H$. As a consequence, the topological phase where gauged BPS baby skyrmions exist, is a higher density phase. For smaller densities, obtained for smaller values of $P$ and $H$, a phase without solitons is reached. We find the critical line in the $P,H$ parameter space. Furthermore, in the soliton phase, we find the equation of state for the baby skyrmion matter $V=V(P,H)$ at zero temperature, where $V$ is the "volume", i.e., area of the solitons.