Phase Transitions in the Two-Dimensional Random Gauge XY Model

Jae-Kwon Kim

Mai Suan Li, Marek Cieplak

Ke Jin, T. L. Chen, Wu-Qun Huang

The Monte Carlo renormalisation group method is applied to discussing the nature of the phase transition of the XY model on a two-dimensional random triangular lattice. A line of fixed points and a nonuniversal phase transition have been found, in agreement with Kosterlitz-Thouless theory.

Tian Wang, T. L. Chen

A generalized XY model with interaction is studied by Monte Carlo renormalization group method on two-dimensional random triangle lattice. For , a line of fixed points has been found. It characterizes that there is a Kosterlitz-Thouless phase transition. For , a first order phase transition has been found. Both of them show the relationship between the nature of phase transition and the class of interactions.

P Reed

The two-dimensional XY model in the presence of random hexagonal anisotropy has been investigated by Monte Carlo simulation. The results indicate the existence of two continuous transitions as the temperature is reduced. Each of the phases is characterised by algebraic decay of the pair correlation functions.

Hassan Chamati, Silvano Romano