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Aging in Spin Glasses in three, four and infinite dimensions

S. Jimenez·V. Martin-Mayor·G. Parisi·A. Tarancon
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Abstract

The SUE machine is used to extend by a factor of 1000 the time-scale of previous studies of the aging, out-of-equilibrium dynamics of the Edwards-Anderson model with binary couplings, on large lattices (L=60). The correlation function, $C(t+t_w,t_w)$, $t_w$ being the time elapsed under a quench from high-temperature, follows nicely a slightly-modified power law for $t>t_w$. Very tiny (logarithmic), yet clearly detectable deviations from the full-aging $t/t_w$ scaling can be observed. Furthermore, the $t<t_w$ data shows clear indications of the presence of more than one time-sector in the aging dynamics. Similar results are found in four-dimensions, but a rather different behaviour is obtained in the infinite-dimensional $z=6$ Viana-Bray model. Most surprisingly, our results in infinite dimensions seem incompatible with dynamical ultrametricity. A detailed study of the link correlation function is presented, suggesting that its aging-properties are the same as for the spin correlation-function.

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S. Jimenez, V. Martin-Mayor, G. Parisi, A. Tarancon. 2003-10-27. Aging in Spin Glasses in three, four and infinite dimensions. https://doi.org/10.1088/0305-4470%2F36%2F43%2F006

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