The link overlap and finite size effects for the 3D Ising spin glass
Theory Group, Department of Physics and Astronomy, University of
Manchester, Manchester M13 9PL, UK
Published online: 15 January 2000
We study the link overlap between two replicas of an Ising spin glass in three dimensions using the Migdal-Kadanoff approximation and scaling arguments based on the droplet picture. For moderate system sizes, the distribution of the link overlap shows the asymmetric shape and large sample-to-sample variations found in Monte-Carlo simulations and usually attributed to replica symmetry breaking. However, the scaling of the width of the distribution, and the link overlap in the presence of a weak coupling between the two replicas are in agreement with the droplet picture. We also discuss why it is impossible to see the asymptotic droplet-like behaviour for moderate system sizes and temperatures not too far below the critical temperature.
PACS: 75.50.Lk – Spin glasses and other random magnets
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2000