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Updated: Jun 21, 2026
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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Hysteresis in the T=0 random-field Ising model: beyond metastable dynamics
Francesc Salvat-Pujol1, Eduard Vives, Martin-Luc Rosinberg
1Departament d'Estructura i Constituents de la Matèria, Facultat de Física, Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona, Catalonia, Spain.
Summary
This study explores the Gaussian random-field Ising model
Area of Science:
- Statistical mechanics
- Condensed matter physics
Background:
- The Gaussian random-field Ising model is a key model for understanding disordered magnetic systems.
- Standard simulations often assume systems remain in metastable states.
Purpose of the Study:
- To investigate the effects of modified dynamics on the zero-temperature response of the Gaussian random-field Ising model.
- To analyze hysteresis and avalanche distributions under these modified conditions.
- To determine if critical exponents of the disorder-induced phase transition are altered.
Main Methods:
- Numerical simulation of the Gaussian random-field Ising model.
- Modification of standard single-spin-flip dynamics to allow trapping in non-metastable configurations.
- Analysis of hysteresis loop and avalanche distributions.
- Finite-size scaling analysis.
Main Results:
- Modified dynamics lead to increased dissipation (hysteresis), mimicking finite driving rates.
- Avalanche distributions along the hysteresis loop were characterized.
- Finite-size scaling analysis provided evidence that critical exponents remain unchanged.
Conclusions:
- The modified dynamics introduce significant hysteresis without altering the fundamental critical exponents of the disorder-induced phase transition.
- This suggests robustness of the critical behavior despite changes in dynamic pathways.
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