title: Stripe-tetragonal phase transition in the two-dimensional Ising model with dipole interactions: partition function zeros approach.
abstract: We have performed multicanonical simulations to study the critical behavior of the two-dimensional Ising model with dipole interactions. This study concerns the thermodynamic phase transitions in the range of the interaction δ where the phase characterized by striped configurations of width h = 1 is observed. Controversial results obtained from local update algorithms have been reported for this region, including the claimed existence of a second-order phase transition line that becomes first order above a tricritical point located somewhere between δ = 0.85 and 1. Our analysis relies on the complex partition function zeros obtained with high statistics from multicanonical simulations. Finite size scaling relations for the leading partition function zeros yield critical exponents ν that are clearly consistent with a single second-order phase transition line, thus excluding such a tricritical point in that region of the phase diagram. This conclusion is further supported by analysis of the specific heat and susceptibility of the orientational order parameter.
authors.affiliation: Departamento de Física, FFCLRP, Universidade de São Paulo, Avenida Bandeirantes, 3900 Ribeirão Preto 14040-901, SP, Brazil. jacyanasaraiva@usp.br
authors.forename: Jacyana S M
authors.initials: JS
authors.lastname: Fonseca
authors.forename: Leandro G
authors.initials: LG
authors.lastname: Rizzi
authors.forename: Nelson A
authors.initials: NA
authors.lastname: Alves
mesh_terms: D003198:Computer Simulation; D008956:Models, Chemical; D015233:Models, Statistical; D044367:Phase Transition