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Updated: Jan 19, 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
8.9K
Field-induced glassy state in disordered cluster antiferromagnets.
M Schmidt1, M V Romitti1, S G Magalhaes2
1Departamento de Física, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil.
Journal of Physics. Condensed Matter : an Institute of Physics Journal
|September 21, 2019
Summary
Antiferromagnetic spin clusters influence magnetic glassiness. Applied fields can induce spin-glass states and increase freezing temperatures, even with weak disorder, offering insights into magnetic materials.
Area of Science:
- Condensed Matter Physics
- Magnetism
- Statistical Mechanics
Background:
- Understanding magnetic glassiness is crucial for developing advanced magnetic materials.
- Antiferromagnetic spin clusters are proposed building blocks in some magnetic systems.
- The influence of external fields on disordered magnetic systems requires further investigation.
Purpose of the Study:
- To investigate the role of antiferromagnetic spin clusters in inducing magnetic glassiness under uniform and random fields.
- To explore the theoretical framework for understanding phenomena in magnetic glassy systems composed of spin clusters.
Main Methods:
- Utilized a replica method to analyze an antiferromagnetic disordered model.
- Reduced the problem to an effective single-cluster model.
- Investigated the effects of uniform and random magnetic fields.
Main Results:
- Weak and intermediate disorder regimes exhibit unusual magnetic phenomena.
- Cluster polarization in a uniform field can favor a cluster spin-glass state, increasing freezing temperature at intermediate disorders.
- Random fields induce local perturbations, supporting cluster freezing even at very weak disorders.
Conclusions:
- The theoretical framework provides insights into magnetic glassy systems with spin clusters.
- Results can explain the field-induced increase in freezing temperature observed in materials like TbIn0.99Mn0.01O3.
- Highlights the importance of spin clusters in magnetic properties of disordered systems.
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