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Memory and superposition in a spin glass

R. Mathieu·P. Jönsson·D. N. H. Nam·P. Nordblad
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Abstract

Non-equilibrium dynamics in a Ag(Mn) spin glass are investigated by measurements of the temperature dependence of the remanent magnetisation. Using specific cooling protocols before recording the thermo- or isothermal remanent magnetisations on re-heating, it is found that the measured curves effectively disclose non-equilibrium spin glass characteristics such as ageing and memory phenomena as well as an extended validity of the superposition principle for the relaxation. The usefulness of this "simple" dc-method is discussed, as well as its applicability to other disordered magnetic systems.

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R. Mathieu, P. Jönsson, D. N. H. Nam, P. Nordblad. 2000-11-17. Memory and superposition in a spin glass. https://doi.org/10.1103/physrevb.63.092401

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