Articulo
Exact solutions for a ferromagnet with Dzyaloshinskii-Moriya interaction
Registro en:
issn:1434-6028
issn:1434-6036
Autor
Grandi, Nicolás Esteban
Lagos, Marcela
Oliva, Julio
Vera, Aldo
Institución
Resumen
On the two-dimensional non-linear Σ-model describing a ferromagnet with Dzyaloshinskii-Moriya interaction, we build three families of exact static solutions depending on a single Cartesian variable. One of them describes a clockwise helix configuration, that characterizes the ground state of the system. A second one corresponds to a counterclockwise helix, representing an excited state. These two families of solutions are parameterized by a continuous parameter that depends on the magnetic field and the Dzyaloshinskii-Moriya coupling. Finally, the third family exists only for isolated values of the same parameter, corresponding to a discrete family of Viviani curves on the target sphere. The degeneracy of the resulting spectrum suggests that an approximate symmetry may emerge at specific values of the magnetic field, at which additional solutions could then exist. Instituto de Física La Plata