Chaotic, memory, and cooling rate effects in spin glasses: Evaluation of the Edwards-Anderson model

We investigate chaotic, memory, and cooling rate effects in the three-dimensional Edwards-Anderson model by doing thermoremanent (TRM) and ac susceptibility numerical experiments and making a detailed comparison with laboratory experiments on spin glasses. In contrast to the experiments, the Edwards-Anderson model does not show any trace of reinitialization processes in temperature change experiments (TRM or ac). A detailed comparison with ac relaxation experiments in the presence of dc magnetic field or coupling distribution perturbations reveals that the absence of chaotic effects in the Edwards-Anderson model is a consequence of the presence of strong cooling rate effects. We discuss possible solutions to this discrepancy, in particular the smallness of the time scales reached in numerical experiments, but we also question the validity of the Edwards-Anderson model to reproduce the experimental results.

[John Rodgers]

Donateur : Nourse, Joseph Everett (1819-19..?)

John Brown Among the Quakers: And Other Sketches, 1904

The Historical Department of Iowa compiled and published these historical papers pertaining to Iowa and the territory from which Iowa was formed. Included are: John Brown among the Quakers, Mascoutin: a reminiscence of the nation of fire, Black Hawk, Keokuk, and their village, Nauvoo and the prophet, the first meeting with the Dakotahs and the tragedy at Minnewaukon.