# Multicritical Nishimori point in the phase diagram of the - J Ising model on a square lattice - Condensed Matter > Disordered Systems and Neural Networks

Multicritical Nishimori point in the phase diagram of the - J Ising model on a square lattice - Condensed Matter > Disordered Systems and Neural Networks - Download this document for free, or read online. Document in PDF available to download.

Abstract: We investigate the critical behavior of the random-bond +- J Ising model on asquare lattice at the multicritical Nishimori point in the T-p phase diagram,where T is the temperature and p is the disorder parameter p=1 corresponds tothe pure Ising model. We perform a finite-size scaling analysis ofhigh-statistics Monte Carlo simulations along the Nishimori line defined by$2p-1={ m Tanh}1-T$, along which the multicritical point lies. Themulticritical Nishimori point is located at p^*=0.890817, T^*=0.95284, andthe renormalization-group dimensions of the operators that control themulticritical behavior are y 1=0.65515 and y 2 = 0.2502; they correspond tothe thermal exponent u= 1-y 2=4.003 and to the crossover exponent \phi=y 1-y 2=2.626.

Author: ** Martin Hasenbusch, Francesco Parisen Toldin, Andrea Pelissetto, Ettore Vicari**

Source: https://arxiv.org/