## Vector chiral phases in frustrated 2D XY model and quantum spin chains    [PDF]

H. Schenck, V. L. Pokrovsky, T. Nattermann
The phase diagram of the frustrated 2D XY model is calculated analytically. The chiral (Ising) transition is described by three independent critical exponents which are calculated in $d=5/2-\epsilon$ dimensions. Vortex interaction is short range on small and logarithmic on large scales, if compared with the chiral correlation length $\xi$. The vortex unbinding transitions is triggered by the increase of $\xi$ and occurs before the chiral transition takes place. In a narrow region close to the Lifshitz point a reentrant quasi-ferromagnetic phase appears. Application to antiferromagnetic quantum spin chains and multiferroics are discussed.
View original: http://arxiv.org/abs/1308.0823