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Non-compact local excitations in spin glasses

J. Lamarcq·J. -P. Bouchaud·O. C. Martin·M. Mezard
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Abstract

We study numerically the local low-energy excitations in the 3-d Edwards-Anderson model for spin glasses. Given the ground state, we determine the lowest-lying connected cluster of flipped spins with a fixed volume containing one given spin. These excitations are not compact, having a fractal dimension close to two, suggesting an analogy with lattice animals. Also, their energy does not grow with their size; the associated exponent is slightly negative whereas the one for compact clusters is positive. These findings call for a modification of the basic hypotheses underlying the droplet model.

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J. Lamarcq, J. -P. Bouchaud, O. C. Martin, M. Mezard. 2002-02-21. Non-compact local excitations in spin glasses. https://doi.org/10.1209/epl%2Fi2002-00641-3

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