Spin-correlation functions of the S=1 Heisenberg-Ising chain by the large-cluster-decomposition Monte Carlo method.

Abstract

We study the spin-correlation functions of the one-dimensional S=1 antiferromagnetic Heisenberg-Ising model by the large-cluster-decomposition Monte Carlo method. It is found that this model shows a second-order transition at the anisotropy parameter ${\ensuremath{\lambda}}_{c}$=1.167\ifmmode\pm\else\textpm\fi{}0.007. The obtained critical exponents (\ensuremath{\eta}=0.253\ifmmode\pm\else\textpm\fi{}0.002, \ensuremath{\beta}=0.126\ifmmode\pm\else\textpm\fi{}0.007, \ensuremath{\nu}=0.98\ifmmode\pm\else\textpm\fi{}0.02) strongly suggest that this transition belongs to the same universality class as the two-dimensional Ising model.