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arXiv · 1205.4200

Ultrametric probe of the spin-glass state in a field

Helmut G. Katzgraber·Thomas Jorg·Florent Krzakala·Alexander K. Hartmann
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Abstract

We study the ultrametric structure of phase space of one-dimensional Ising spin glasses with random power-law interaction in an external random field. Although in zero field the model in both the mean-field and non-mean-field universality classes shows an ultrametric signature [Phys. Rev. Lett. 102, 037207 (2009)], when a field is applied ultrametricity seems only present in the mean-field regime. The results for the non-mean field case in an external field agree with data for spin glasses studied within the Migdal-Kadanoff approximation. Our results therefore suggest that the spin-glass state might be fragile to external fields below the upper critical dimension.

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Helmut G. Katzgraber, Thomas Jorg, Florent Krzakala, Alexander K. Hartmann. 2012-11-06. Ultrametric probe of the spin-glass state in a field. https://doi.org/10.1103/physrevb.86.184405

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