Transitions and crossover phenomena in fully frustrated XY systems
Abstract
We study the two-dimensional fully frustrated XY (FFXY) model and two related models, a discretization of the Landau-Ginzburg-Wilson Hamiltonian for the critical modes of the FFXY model and a coupled Ising- XY model, by means of Monte Carlo simulations on square lattices L2 , L≲103 . We show that their phase diagram is characterized by two very close chiral and spin transitions, at Tch>Tsp respectively, of the Ising and Kosterlitz-Thouless type. At Tch the Ising regime sets in only after a preasymptotic regime, which appears universal to some extent. The approach is nonmonotonic for most observables, with a wide region controlled by an effective exponent νeff≈0.8 .
- Publication:
-
Physical Review B
- Pub Date:
- November 2005
- DOI:
- 10.1103/PhysRevB.72.184502
- arXiv:
- arXiv:cond-mat/0506345
- Bibcode:
- 2005PhRvB..72r4502H
- Keywords:
-
- 74.81.Fa;
- 64.60.-i;
- 64.60.Fr;
- 75.10.Hk;
- Josephson junction arrays and wire networks;
- General studies of phase transitions;
- Equilibrium properties near critical points critical exponents;
- Classical spin models;
- Condensed Matter - Statistical Mechanics;
- High Energy Physics - Lattice
- E-Print:
- 9 pages