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arXiv · 0706.2423

Finite versus zero-temperature hysteretic behavior of spin glasses: Experiment and theory

Abstract

We present experimental results attempting to fingerprint nonanalyticities in the magnetization curves of spin glasses found by Katzgraber et al. [Phys. Rev. Lett. 89, 257202 (2002)] via zero-temperature Monte Carlo simulations of the Edwards-Anderson Ising spin glass. Our results show that the singularities at zero temperature due to the reversal-field memory effect are washed out by the finite temperatures of the experiments. The data are analyzed via the first order reversal curve (FORC) magnetic fingerprinting method. The experimental results are supported by Monte Carlo simulations of the Edwards-Anderson Ising spin glass at finite temperatures which agree qualitatively very well with the experimental results. This suggests that the hysteretic behavior of real Ising spin-glass materials is well described by the Edwards-Anderson Ising spin glass. Furthermore, reversal-field memory is a purely zero-temperature effect.

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BibTeXRIS

Helmut G. Katzgraber, D. Herisson, M. Oesth, Per Nordblad, Atsuko Ito, Hiroko Aruga Katori. 2007-09-30. Finite versus zero-temperature hysteretic behavior of spin glasses: Experiment and theory. https://doi.org/10.1103/physrevb.76.092408

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