Off-equilibrium fluctuation-dissipation relation in a spin glass
نویسندگان
چکیده
We report new experimental results obtained on the insulating spin glass CdCr1.7In0.3S4. Our experimental setup allows a quantitative comparison between the thermo-remanent magnetisation and the autocorrelation of spontaneous fluctuations of magnetisation, yielding a complete determination of the fluctuation-dissipation relation. The dynamics can be studied both in the quasi-equilibrium regime, where the fluctuation-dissipation theorem holds, and in the deeply ageing regime. The limit of separation of time-scales, as used in analytical calculations, can be approached by use of a scaling procedure. PACS. 05.70.Ln Non-equilibrium and irreversible thermodynamics – 75.50.Lk Spin glasses and other random magnets – 07.20.Dt Thermometers – 07.55.Jg Magnetometers for susceptibility, magnetic moment, and magnetisation measurements
منابع مشابه
Off-equilibrium fluctuation-dissipation relation in a spin glass An experimental test for mean-field predictions
We report new experimental results obtained on the insulating spin glass CdCr1.7In0.3S4. Our experimental setup allows a quantitative comparison between the thermo-remanent magnetisation and the autocorrelation of spontaneous fluctuations of magnetisation, yielding a complete determination of the fluctuation-dissipation relation. The dynamics can be studied both in the quasi-equilibrium regime,...
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