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Updated: Jun 16, 2026
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Sputter Growth and Characterization of Metamagnetic B2-ordered FeRh Epilayers
Published on: October 5, 2013
Switchable hardening of a ferromagnet at fixed temperature
D M Silevitch1, G Aeppli, T F Rosenbaum
1The James Franck Institute and Department of Physics, The University of Chicago, 929 East 57th Street, Chicago, IL 60637, USA.
Summary
External magnetic fields can control magnetic domain structures in disordered ferromagnets. This research reveals how transverse fields regulate domain pinning and domain wall dynamics, offering insights into magnetic materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism
Background:
- The domain structure of magnetic materials is critical for applications like data storage and power conversion.
- Traditionally, domain structures are established during material synthesis.
Purpose of the Study:
- To investigate the role of external magnetic fields in regulating domain pinning and domain wall dynamics.
- To explore the isothermal control of domain structure in disordered uniaxial ferromagnets.
Main Methods:
- Applying external magnetic fields transverse to the magnetization of a model disordered uniaxial ferromagnet.
- Observing domain pinning and domain wall behavior at varying temperatures, including near the paramagnetic transition.
Main Results:
- Transverse magnetic fields act as isothermal regulators of domain pinning.
- At elevated temperatures, modest fields increase pinning and stabilize the domain structure, hardening the magnet.
- At higher fields, quantum tunneling of domain walls occurs, softening the magnet.
Conclusions:
- Quantum tunneling of domain walls dominates dynamics at low temperatures.
- The quantum phase transition in disordered magnets can be interpreted as a domain wall localization/delocalization transition.
- The discovered principles are general and applicable to anisotropic ferromagnets with higher ordering temperatures.
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