arXiv:cond-mat/9612140 · Physical Review Letters
Domain Walls and Phase Transitions in the Frustrated Two-Dimensional XY Model
Colin Denniston B, Chao Tang
Abstract
We compare the critical properties of the two-dimensional (2D) $\mathrm{XY}$ model in a transverse magnetic field with filling factors $f\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1/3$ and $2/5$. To obtain a comparison with recent experiments, we investigate the effect of weak quenched bond disorder for $f\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2/5$. A finite-size scaling analysis of extensive Monte Carlo simulations strongly suggests that the critical exponents of the phase transition for $f\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1/3$, and for $f\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2/5$ with disorder, are those of the pure 2D Ising model. Studying the possible domain walls in the system provides some explanations for our results.