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Optically and Microwave-Induced Magnetization Precession in [Co/Pt]/NiFe Exchange Springs
Maciej Da Browski1, Andreas Frisk2, David M Burn2
1Department of Physics and Astronomy, University of Exeter, Stocker Road, Exeter, Devon EX4 4QL, U.K.
ACS Applied Materials & Interfaces
|November 6, 2020
Summary
Non-collinear spin structures in [Co/Pt]/NiFe enhance magnetic recording. Optically stimulated magnetization precession was observed, paving the way for ultrafast magnetic recording and spintronics.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Microwave-assisted and heat-assisted magnetic recording technologies increase hard disk drive capacity.
- Non-collinear spin structures combining perpendicular and in-plane magnetic anisotropy can improve magnetic recording efficiency.
Purpose of the Study:
- Investigate microwave and optically excited magnetization dynamics in [Co/Pt]/NiFe exchange spring samples.
- Explore the role of canted magnetization in the interfacial region for optical control of magnetization.
Main Methods:
- Fabrication of [Co/Pt]/NiFe exchange spring samples.
- Experimental investigation of magnetization dynamics using microwave and optical excitation.
- Analysis of magnetic field and frequency response.
Main Results:
- Observed optically stimulated magnetization precession over an extended magnetic field and frequency range.
- Demonstrated that canted magnetization in the interfacial region enables this precession.
- Explained results by the formation of an imprinted domain structure that enhances robustness.
Conclusions:
- Tuning the canted interfacial domain structure offers enhanced control over optically excited magnetization reversal.
- Potential for developing ultrafast magnetic recording and spintronic devices.
- Imprinted domain structures provide robustness against external perturbations.
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