Quasi-long-range order in the 2D XY model with random phase shifts

We study the square-lattice XY model in the presence of random phase shifts. We consider two different disorder distributions with zero average shift and investigate the low-temperature quasi-long-range order phase which occurs for sufficiently low disorder. By means of Monte Carlo simulations we determine several universal quantities, which are then compared with the analytic predictions of the random spin-wave theory. We observe a very good agreement which indicates that the universal long-distance behaviour in the whole low-disorder low-temperature phase is fully described by the random spin-wave theory. © 2009 IOP Publishing Ltd.