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Fluctuation-dissipation ratio of the Heisenberg spin glass

Hikaru Kawamura
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Abstract

Fluctuation-dissipation (FD) relation of the three-dimensional Heisenberg spin glass with weak random anisotropy is studied by off-equilibrium Monte Carlo simulation. Numerically determined FD ratio exhibits a ``one-step-ike''behavior, the effective temperature of the spin-glass state being about twice the spin-glass transition temperature, $T_{\rm eff}\simeq 2T_g$, irrespective of the bath temperature. The results are discussed in conjunction with the recent experiment by Herisson and Ocio, and with the chirality scenario of spin-glass transition.

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Hikaru Kawamura. 2003-06-10. Fluctuation-dissipation ratio of the Heisenberg spin glass. https://doi.org/10.1103/physrevlett.90.237201

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