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Updated: Oct 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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Memory effect and phase transition in a hierarchical trap model for spin glasses
Depei Zhang1, Tianran Chen1, Marija Vucelja1
1Department of Physics, University of Virginia, Charlottesville, Virginia 22904, USA.
Physical Review. E
|January 15, 2022
Summary
We demonstrate the thermoremanent magnetization memory effect using a dynamical tree method. This study reveals a link between hierarchical structures, condensation phenomena, and glassy behavior in magnetic systems.
Area of Science:
- Condensed Matter Physics
- Statistical Mechanics
- Geophysics (Paleomagnetism)
Background:
- The thermoremanent magnetization (TRM) memory effect is a key phenomenon in paleomagnetism, reflecting the magnetic history of materials.
- Understanding nonequilibrium phenomena in hierarchical energy landscapes is crucial for explaining complex magnetic behaviors.
- Previous models often struggle to capture the intricate waiting-time and temperature dependencies observed in TRM.
Purpose of the Study:
- To introduce an efficient dynamical tree method for simulating the TRM memory effect.
- To explicitly demonstrate the TRM memory effect within a hierarchical energy landscape.
- To investigate the condensation effect and its relationship with structural properties in magnetic systems.
Main Methods:
- Development and application of an efficient dynamical tree method.
- Nonequilibrium simulations to reproduce waiting-time and waiting-temperature dependences.
- Analysis of the multilayer trap model to study the condensation effect.
Main Results:
- Successfully demonstrated the thermoremanent magnetization memory effect in a hierarchical energy landscape.
- Reproduced nontrivial waiting-time and waiting-temperature dependences characteristic of this nonequilibrium phenomenon.
- Observed that a structural phase transition in the multilayer tree model coincides with the onset of the condensation effect.
Conclusions:
- The study highlights the critical role of hierarchical structures in governing magnetic memory effects.
- A strong relationship exists between glassy behavior and the underlying structure of barrier trees.
- The condensation phenomenon, where few microstates dominate, is intimately linked to the system's hierarchical organization.
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