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

TL;DR

This paper compares experimental and theoretical analyses of hysteretic behavior in spin glasses, showing that zero-temperature singularities are washed out at finite temperatures, and that the Edwards-Anderson model effectively describes real materials.

Contribution

It demonstrates that finite-temperature effects eliminate zero-temperature singularities in spin glasses and validates the Edwards-Anderson model for real material behavior.

Findings

Zero-temperature singularities are washed out at finite temperatures.

Monte Carlo simulations agree qualitatively with experimental data.

Reversal-field memory is a zero-temperature phenomenon.

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.