The Critical Exponent η of the Three-Dimensional ±J Ising Model by the Transfer Matrix Method

The three-dimensional ± J Ising model on the simple cubic lattice is studied by means of the screw transfer matrix method for L × L × N lattices ( L =2∼5; N ≃10 3 ). Studying the decay of the correlation functions, the value of the critical exponent η is found to be -0.26±0.03, assuming T sg / J =1.2. The result is in good agreement with that obtained by the Monte Carlo method and high temperature series expansion method.