Numerical results for the Edwards-Anderson spin-glass model at low temperature

J. F. Fernández, J. J. Alonso

Published 2013-04-29Version 1

We have simulated Edwards-Anderson (EA) as well as Sherrington-Kirkpatrick systems of L^3 spins. After averaging over large sets of EA system samples of 3 =< L =< 10, we obtain accurate numbers for distributions p(q) of the overlap parameter q at very low temperature T. We find p(0)/T --> 0.233(4) as T --> 0. This is in contrast with the droplet scenario of spin glasses. We also study the number of mismatched links --between replica pairs-- that come with large scale excitations. Contributions from small scale excitations are discarded. We thus obtain for the fractal dimension of outer surfaces of q~0 excitations in the EA model d_s --> 2.59(3) as T tends to 0. This is in contrast with d_s --> 3 as T --> 0 that is predicted by mean field theory for the macroscopic limit.