Thermal destruction of chiral order in a two-dimensional model of coupled trihedra
| dc.creator | Messio, Laura | |
| dc.creator | Domenge, Jean-Christophe | |
| dc.creator | Lhuillier, Claire | |
| dc.creator | Pierre, Laurent | |
| dc.creator | Viot, Pascal | |
| dc.creator | Misguich, Gregoire | |
| dc.date | 2008-06-13 | |
| dc.date.accessioned | 2026-07-07T12:12:35Z | |
| dc.date.available | 2026-07-07T12:12:35Z | |
| dc.description | We introduce a minimal model describing the physics of classical two-dimensional (2D) frustrated Heisenberg systems, where spins order in a non-planar way at T=0. This model, consisting of coupled trihedra (or Ising-$\mathbb{R}P^3$ model), encompasses Ising (chiral) degrees of freedom, spin-wave excitations and $\Z_2$ vortices. Extensive Monte Carlo simulations show that the T=0 chiral order disappears at finite temperature in a continuous phase transition in the 2D Ising universality class, despite misleading intermediate-size effects observed at the transition. The analysis of configurations reveals that short-range spin fluctuations and $\Z_2$ vortices proliferate near the chiral domain walls explaining the strong renormalization of the transition temperature. Chiral domain walls can themselves carry an unlocalized $\Z_2$ topological charge, and vortices are then preferentially paired with charged walls. Further, we conjecture that the anomalous size-effects suggest the proximity of the present model to a tricritical point. A body of results is presented, that all support this claim: (i) First-order transitions obtained by Monte Carlo simulations on several related models (ii) Approximate mapping between the Ising-$\mathbb{R}P^3$ model and a dilute Ising model (exhibiting a tricritical point) and, finally, (iii) Mean-field results obtained for Ising-multispin Hamiltonians, derived from the high-temperature expansion for the vector spins of the Ising-$\mathbb{R}P^3$ model. | |
| dc.description | 15 pages, 12 figures, 1 table | |
| dc.identifier | https://arxiv.org/abs/0806.2259 | |
| dc.identifier | http://arxiv.org/abs/0806.2259 | |
| dc.identifier | Phys. Rev. B 78, 054435 (2008) | |
| dc.identifier | doi:10.1103/PhysRevB.78.054435 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/210594 | |
| dc.subject | Statistical Mechanics | |
| dc.title | Thermal destruction of chiral order in a two-dimensional model of coupled trihedra | |
| dc.type | text |