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Loss separation for dynamic hysteresis in ferromagnetic thin films
Francesca Colaiori1, Gianfranco Durin, Stefano Zapperi
1CNR-INFM, SMC, Dipartimento di Fisica, Università La Sapienza, P.le A. Moro 2, 00185 Roma, Italy.
Physical Review Letters
|February 7, 2007
Summary
A new theory explains dynamic hysteresis in ferromagnetic thin films using loss separation, applicable to disordered magnetic systems. This model successfully reconciles experimental data across various materials and frequencies.
Area of Science:
- Physics
- Materials Science
- Magnetism
Background:
- Dynamic hysteresis in ferromagnetic thin films is complex.
- Existing theories often lack universality across different materials.
- Disordered magnetic systems present unique challenges.
Purpose of the Study:
- To develop a universal theory for dynamic hysteresis in ferromagnetic thin films.
- To demonstrate the applicability of loss separation to disordered magnetic systems.
- To reconcile experimental observations of dynamic hysteresis.
Main Methods:
- Developed a theory based on the phenomenological principle of loss separation.
- Performed numerical simulations using a driven random-field Ising model.
- Reexamined existing experimental data on thin film hysteresis.
Main Results:
- The loss separation theory is applicable to disordered magnetic systems.
- Simulations and experimental data align with the developed theory.
- The theory accurately predicts power loss dependence on driving field rate across frequencies.
Conclusions:
- Loss separation provides a unifying framework for dynamic hysteresis in ferromagnetic thin films.
- The theory reconciles the apparent lack of universality in experimental data.
- This approach offers a general explanation for magnetic damping mechanisms.
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