Monte Carlo study of the XY-model on Sierpinski gasket

Abstract: We have performed a Monte Carlo study of the classical XY-model on two-dimensional Sierpinski gaskets of several cluster sizes. From the dependence of the helicity modulus on the cluster size we conclude that there is no phase transition in this system at a finite temperature. This is in agreement with previous findings for the harmonic approximation to the XY-model on Sierpinski gasket and is analogous to the absence of finite temperature phase transition for the Ising model on fractals with a finite order of ramification.