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Oscillatory decay of magnetization induced by domain-wall stray fields
1IBM Research Division, Almaden Research Center, San Jose, California 95120-6099, USA.
Physical Review Letters
|October 6, 2000
Summary
We observed an unusual oscillatory decay in hard ferromagnetic layers during demagnetization. This phenomenon, driven by soft layer domain wall fields, was confirmed using advanced imaging and simulations.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Magnetism
Background:
- Ferromagnetic layers are crucial in magnetic storage devices.
- Understanding layer interactions is key to improving device performance.
- Domain wall dynamics influence magnetic behavior.
Purpose of the Study:
- To investigate the demagnetization process of a hard ferromagnetic layer.
- To analyze the effect of a neighboring soft ferromagnetic layer's domain walls.
- To understand the mechanism behind an observed oscillatory decay.
Main Methods:
- Experimental exploration of ferromagnetic layer demagnetization.
- Utilizing structures for controlled magnetic moment reversal.
- High-resolution photoemission electron microscopy (HREM) for imaging.
- Micromagnetic simulations for theoretical validation.
Main Results:
- Observed an unusual oscillatory decay in the hard layer's magnetic moment.
- Demagnetization occurred after several hundred cycles.
- Microscopic imaging confirmed the magnetization behavior.
- Simulations corroborated the experimental findings.
Conclusions:
- The fringing fields from a soft layer's domain walls can demagnetize a hard layer.
- An unexpected oscillatory decay pattern was identified.
- HREM and micromagnetic simulations validated this novel demagnetization behavior.
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