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Updated: Jul 6, 2025
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
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Multifractality in spin glasses
Marco Baity-Jesi1, Enrico Calore2, Andrés Cruz3,4
1Eawag, CH-8600 Dübendorf, Switzerland.
Summary
We discovered multifractal behavior in Ising spin glasses at low temperatures. Dramatic fluctuations were observed, challenging previous assumptions about spin-glass dynamics and revealing new insights into their complex correlations.
Area of Science:
- Condensed matter physics
- Statistical mechanics
Background:
- Spin glasses exhibit complex dynamics at low temperatures.
- Understanding their correlation functions is crucial for characterizing their behavior.
Purpose of the Study:
- To investigate the multifractal behavior of Ising spin glasses in their low-temperature phase.
- To reconcile observed dramatic fluctuations with established self-averaging models.
Main Methods:
- Utilized the Janus II supercomputer for local analysis of the spin-glass correlation function.
- Computed the singularity spectrum and its Legendre transform to characterize fluctuation scaling.
Main Results:
- Identified dramatic fluctuations in spin-glass correlations at short length scales.
- Found that a small subset of site pairs governs the average correlation.
- Demonstrated multifractal scaling of these fluctuations as coherence length grows.
Conclusions:
- The low-temperature phase of Ising spin glasses exhibits multifractal characteristics.
- Dramatic local fluctuations are reconciled with overall smooth, self-averaging behavior.
- New understanding of spin-glass dynamics and magnetic field response.
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