Strong Dynamical Heterogeneities in the Violation of the Fluctuation-Dissipation Theorem in Spin Glasses

Abstract

We analyze numerically the violation of the fluctuation-dissipation theorem (FDT) in the $\pm J$ Edwards-Anderson (EA) spin glass model. Using single spin probability densities we reveal the presence of strong dynamical heterogeneities, which correlate with ground state information. The physical interpretation of the results shows that the spins in the EA model can be divided in two sets. In 3D, one set forms a compact structure which presents a coarsening-like behavior with its characteristic violation of the FDT, while the other asymptotically follows the FDT. Finally, we compare the dynamical behavior observed in 3D with 2D.

Accepted for publication in Phys. Rev. Lett. 2007