Self-dual solitons in a $CPT$-odd and Lorentz-violating gauged $O(3)$ sigma model

TL;DR

This paper studies self-dual vortex solutions in a Lorentz-violating gauged $O(3)$ sigma model, revealing how Lorentz violation influences energy, magnetic flux, and field profiles, and interpolates between different sigma models.

Contribution

It introduces a complete analysis of self-dual configurations in a Lorentz-violating gauged $O(3)$ sigma model, deriving first-order equations and exploring the effects of Lorentz violation.

Findings

Energy and magnetic flux depend on Lorentz-violating coefficients.

Lorentz violation increases magnetic field and energy density near the origin.

The model interpolates between Lorentz-violating sigma and Maxwell-Chern-Simons sigma models.

Abstract

We have performed a complete study of self-dual configurations in a $CPT$-odd and Lorentz-violating gauged $O(3)$ nonlinear sigma model. We have consistently implemented the Bogomol'nyi-Prasad-Sommerfield (BPS) formalism and obtained the correspondent differential first-order equations describing electrically charged self-dual configurations. The total energy and magnetic flux of the vortices, besides being proportional to the winding number, also depend explicitly on the Lorentz-violating coefficients belonging to the sigma sector. The total electrical charge is proportional to the magnetic flux such as it occurs in Chern-Simons models. The Lorentz violation in the sigma sector allows one to interpolate between Lorentz-violating versions of some sigma models: the gauged $O(3)$ sigma model and the Maxwell-Chern-Simons $O(3)$ sigma model. The Lorentz violation enhances the amplitude of the magnetic field and BPS energy density near the origin, augmenting the deviation in relation to the solutions deprived of Lorentz violation.