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Memory and Chaos Effects in Spin Glasses

K. Jonason·E. Vincent·J. Hammann·J. P. Bouchaud·P. Nordblad
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Abstract

New low frequency ac susceptibility measurements on two different spin glasses show that cooling/heating the sample at a constant rate yields an essentially reversible (but rate dependent) X(T) curve; a downward relaxation of X occurs during a temporary stop at constant temperature (ageing). Two main features of our results are: (i)when cooling is resumed after such a stop, X goes back to the reversible curve (chaos) (ii) upon re-heating, X perfectly traces the previous ageing history (memory). We discuss implications of our results for a real space (as opposed to phase space) picture of spin glasses.

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K. Jonason, E. Vincent, J. Hammann, J. P. Bouchaud, P. Nordblad. 1998-09-01. Memory and Chaos Effects in Spin Glasses. https://doi.org/10.1103/physrevlett.81.3243

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