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Towards an experimental measure of the number of metastable states in spin-glasses ?

J. P. Bouchaud·E. Vincent·J. Hammann
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Abstract

We show that an 'ergodic' time scale can be extracted from the aging experiments on spin-glasses. This is the time for which a significant fraction of the metastable states have been visited. Experiments suggest that the number of metastable states per independent subsystem is $\simeq 10^{12}-10^{14}$. For our insulating spin-glass $({\rm CdCr}_{1.7} {\rm In}_{0.3} {\rm S}_4)$ this number doubles when the temperature is lowered by 1K, but is roughly constant for the metallic sample (Ag:Mn 2.6%).

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J. P. Bouchaud, E. Vincent, J. Hammann. 1993-03-12. Towards an experimental measure of the number of metastable states in spin-glasses ?. https://doi.org/10.1051/jp1%3A1994127

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