INSTITUTO DE FISICA DE LIQUIDOS Y SISTEMAS BIOLOGICOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Multicritical Behavior in the Ising Model with Dipolar Interactions
M. L. RUBIO PUZZO; C. M. HOROWITZ; M. A. BAB; G. P. SARACCO
Congreso; Fronteirs in Physical Sciences Humboldt Kolleg; 2016
In this work, the phase diagram of the ferromagnetic Ising model with dipole interactions is revisited with the aim of determining the nature of the phase transition between the stripe-ordered with width n (h=n) and tetragonal liquid (TL) phases. Extensive Monte Carlo simulations are performed in order to study the short-time dynamic behavior of the observables for selected values of the ratio between the ferromagnetic exchange and dipolar constants, δ. The obtained results indicate that the h=1-TL phase transition line is continuous up to δ=1.2585, while for the h=2?TL line a weak first-order character is found in the interval 1.2585≤δ≤1.36 and becomes continuous for 1.37≤δ≤1.9. This result suggests the existence of a tricritical point close to δ=1.37. When it is appropriate, the complete set of the critical exponents is obtained, and in all the studied cases they depend on δ but do not belong to the Ising universality class. Furthermore, short-time dynamic studies reveal that at the point where the mentioned lines meet with the h=1-h=2 line, i.e.,at δ=1.2585, the critical phase corresponding to the h=1?TL transition coexists with the h=2 phase.