Critical properties of the three-dimensional XY model in large-scale Monte-Carlo simulations

The critical properties of the three-dimensional XY model are studied in large-scale Monte-Carlo simulations by using a worm algorithm for the integer-current representation of the model. In large systems, singular behavior of the internal energy around the critical point is observed, and the finite-size scaling analyses of the superfluid stiffness lead us to find the critical inverse temperature Kc = 0.45416(1) and the correlation length critical exponent ν = 0.6708(5).