Off-equilibrium fluctuation-dissipation relation in a spin glass An experimental test for mean-field predictions
نویسنده
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
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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The out of equilibrium dynamics of finite dimensional spin glasses is considered from a point of view going beyond the standard ‘mean-field theory’ versus ‘droplet picture’ debate of the last decades. The main predictions of both theories concerning the spin glass dynamics are discussed. It is shown, in particular, that predictions originating from mean-field ideas concerning the violations of ...
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