Evidence of a Spin-Glass Phase Transition ofa Site-Random Ising Model in Two Dimensions

Abstract

We study a site-random Ising (SRI) model in two dimensions (2D) using a Monte Carlo method. It is found that the Binder parameter g_L's for different sizes of the lattice L come together at almost the same temperature as in the ± J model in 3D. Finite-size scaling analyses give results which are compatible with the assumption of a finite, nonzero transition temperature (T_c≠ 0), although the scaling temperature range is not large. We suggest that in the SRI model a spin glass (SG) phase transition occurs at T_c≠ 0 even in 2D.