title: Nature of long-range order in stripe-forming systems with long-range repulsive interactions.
abstract: We study two dimensional stripe forming systems with competing repulsive interactions decaying as r(-α). We derive an effective Hamiltonian with a short-range part and a generalized dipolar interaction which depends on the exponent α. An approximate map of this model to a known XY model with dipolar interactions allows us to conclude that, for α<2 long-range orientational order of stripes can exist in two dimensions, and establish the universality class of the models. When α≥2 no long-range order is possible, but a phase transition in the Kosterlitz-Thouless universality class is still present. These two different critical scenarios should be observed in experimentally relevant two dimensional systems like electronic liquids (α=1) and dipolar magnetic films (α=3). Results from Langevin simulations of Coulomb and dipolar systems give support to the theoretical results.
authors.affiliation: Departamento de Física, Universidade Federal do Rio Grande do Sul, CP 15051, 91501-970 Porto Alegre, RS, Brazil.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Mendoza-Coto
authors.affiliation: Departamento de Física, Universidade Federal do Rio Grande do Sul and National Institute of Science and Technology for Complex Systems, CP 15051, 91501-970 Porto Alegre, RS, Brazil.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Stariolo
authors.affiliation: Departamento de Física, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC, Brazil.
authors.forename: Lucas
authors.initials: L
authors.lastname: Nicolao