Abstract
Violation of the fluctuation-dissipation theorem (FDT) in a frustrated Heisenberg model on the kagomé lattice is investigated using Monte Carlo simulations. The model exhibits glassy behavior at low temperatures accompanied by very slow dynamics. Both the spin-spin autocorrelation function and the response to an external magnetic field are studied. Clear evidence of a constant value of the fluctuation-dissipation ratio and long-range memory effects is observed in this model. The breakdown of the FDT in the glassy phase follows the predictions of mean-field theory for spin glasses with one-step replica symmetry breaking.
- Received 27 February 2003
DOI:https://doi.org/10.1103/PhysRevB.67.212406
©2003 American Physical Society