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Anisotropy constants of magnetic materials are typically determined through angle-resolved Ferromagnetic Resonance (ar-FMR) and torque magnetometry, which can be time consuming measurements, thus limiting their utility. The Stoner–Wohlfarth model can be used to numerically fit measured magnetic hysteresis curves to more easily determine these anisotropy constants. To demonstrate this, 10 nm bct FexCoyMnz single-crystal films grown by molecular beam epitaxy on MgO(001) substrates were investigated. The hysteresis behavior measured by vibrating sample magnetometry was least-squares fit against numerically calculated hysteresis curves generated from the Stoner–Wohlfarth model to extract the anisotropy constants. The cubic anisotropy of different compositions of FeCoMn films was at ∼104 J/m3, which is on the same order of magnitude of bct Fe and Co thin films measured by ar-FMR and torque magnetometry techniques.
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Modification of magnetocrystalline anisotropy via ion-implantation
The ability to systematically modify the magnetic properties of epitaxial La0.7Sr0.3MnO3 thin films is demonstrated through the use of Ar+ ion implantation. With increasing implant dose, a uniaxial expansion of the c-axis of the unit cell leads to a transition from in-plane toward perpendicular magnetic anisotropy. Above a critical dose of 3 × 1013 Ar+/cm2, significant crystalline disorder exists leading to a decrease in the average Mn valence state and near complete suppression of magnetization. Combined with lithographic techniques, ion implantation enables the fabrication of magnetic spin textures consisting of adjacent regions with tunable magnetic anisotropy in complex oxide thin films.
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- PAR ID:
- 10597337
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- AIP Advances
- Volume:
- 10
- Issue:
- 4
- ISSN:
- 2158-3226
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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