arXiv subjects

A. J. Balseyro Sebastian

Publications and source records attributed to A. J. Balseyro Sebastian.

7 recordsLinked to original sources

arXiv2026

Magnetic Q-balls

We study charged soliton branches in quasi-one-dimensional chiral magnetic systems with Dzyaloshinskii--Moriya (DM) interaction, easy-axis anisotropy, and Zeeman coupling. The same static magnetic functional is equipped with two different dynamical completions: an antiferromagnetic model with second-order time derivatives and a ferromagnetic model with Berry-phase dynamics. On the helical branch selected by the static DM interaction, the problem reduces to an analytically tractable one-dimensional system for the polar angle of the order parameter. We derive the existence conditions for polar Q-balls from the curvature of the reduced effective potential and the presence of a nonzero turning point. In the antiferromagnetic case, the allowed frequency window is symmetric and can be completely closed by the combined effect of the DM coupling and the Zeeman field. At zero Zeeman field, the same reduction also supports antiferromagnetic Q-kinks, for which we obtain explicit profiles, charges, energies, and reduced-sector fission criteria. In the ferromagnetic case, the Berry phase makes the rotation frequency act as a shifted Zeeman field. As a result, north- and south-pole charged droplets are selected by opposite signs of the shifted rotation. We also show that a formal pole-to-pole solution of the ferromagnetic mechanical problem does not generally correspond to a finite-energy magnetic soliton, because the Berry term does not renormalize the physical Hamiltonian. These results clarify how charged-soliton mechanisms depend on the underlying magnetic dynamics, even when the static chiral energy is the same.

cond-mat.mes-hall↗

arXiv2025

Kinks in composite scalar field theories

In this work, families of kinks are analytically identified in multifield theories with either polynomial or deformed sine-Gordon-type potentials. The underlying procedure not only allows us to obtain analytical solutions for these models, but also provides a framework for constructing more general families of field theories that inherit certain analytical information about their solutions. Specifically, this method combines two known field theories into a new composite field theory whose target space is the product of the original target spaces. By suitably coupling the fields through a superpotential defined on the product space, the dynamics in the subspaces become entangled while preserving original kinks as boundary kinks. Different composite field theories are studied, including extensions of well-known models to wider target spaces.

hep-th↗

arXiv2024

Transference of kinks between $\mathbb{S}^2$ and $\mathbb{R}^2$ Sigma models

In this paper methods for deforming scalar field theories on Euclidean target spaces, in which new field theories are constructed so that solutions are known, are generalized to the context of Sigma models. In particular, deformations between Sigma models on the plane and on the sphere are considered. Three different examples are presented, where the change in the structure of the kink variety and the energy of the deformed kinks during this procedure are studied.

hep-th↗

arXiv2023

Topological and non-topological kink families in non-linear $(\mathbb{S}^1\times \mathbb{S}^1)$-Sigma models

In this paper we construct a family of Hamilton-Jacobi separable non-linear $\mathbb{S}^1\times\mathbb{S}^1$ Sigma models for which the kink variety can be analytically identified and for which the linear stability of the emerging kinks is ensured. Furthermore, a model with only one vacuum point is found, where all kinks are forced to be non-topological. The non-simply connectedness of the torus guarantees the global stability of all the non-topological kinks in these models.

hep-th↗

arXiv2023

Mechanism to induce geometric constriction on kinks and domain walls

We investigate scalar field theories in the multifield scenario, focusing mainly on the possibility to smoothly build internal structure and asymmetry for kinks and domain walls. The procedure requires the inclusion of an extra field which is associated to a function that modifies the dynamics of the other fields. We investigate minimum energy configurations, which support first order equations compatible with the equations of motion. The extra field allows a transition which is guided by a parameter that connects the standard solution to another one, geometrically constrained, mimicking the effects of geometrical constrictions in magnetic materials.

hep-th↗

arXiv2022

Kinks in massive non-linear ${\mathbb S}^1\times{\mathbb S}^1$-Sigma models

In this paper the whole kink varieties arising in several massive non-linear Sigma models whose target space is the torus ${\mathbb S}^1\times{\mathbb S}^1$ are analytically calculated. This possibility underlies the construction of first-order differential equations by adapting the Bogomolny procedure to non-Euclidean spaces. Among the families of solutions non-topological kinks connecting the same vacuum are found. This class of solutions are usually considered to be not globally stable. However, in this context the topological constraints obtained by the non-simply connectedness of the target space turn these non-topological kinks into globally stable solutions. The analytical resolution of the equations allows the complete study of the linear stability for some basic kinks.

nlin.PS↗

arXiv2018

Domain walls in a non-linear $\mathbb{S}^2$-sigma model with homogeneous quartic polynomial potential

In this paper the domain wall solutions of a Ginzburg-Landau non-linear $\mathbb{S}^2$-sigma hybrid model are exactly calculated. There exist two types of basic domain walls and two families of composite domain walls. The domain wall solutions have been identified by using a Bogomolny arrangement in a system of sphero-conical coordinates on the sphere $\mathbb{S}^2$. The stability of all the domain walls is also investigated.

hep-th↗