XMCD studies of Co and Co–Pt nanoparticles prepared by vapour deposition
| Autor: | José Penuelas, Josep Penuelas, Caroline ANDREAZZA-VIGNOLLE, Pascal Andreazza, Paolo Imperia, Detlef Schmitz |
|---|---|
| Přispěvatelé: | INL - Hétéroepitaxie et Nanostructures (INL - H&N), Institut des Nanotechnologies de Lyon (INL), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-École supérieure de Chimie Physique Electronique de Lyon (CPE)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Lyon (ECL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherche sur la Matière Divisée (CRMD), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO) |
| Jazyk: | angličtina |
| Rok vydání: | 2007 |
| Předmět: |
Materials science
Magnetic circular dichroism Analytical chemistry Oxide Nanoparticle 02 engineering and technology Crystal structure Vapour deposition 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences Electronic Optical and Magnetic Materials chemistry.chemical_compound Nuclear magnetic resonance chemistry 0103 physical sciences Magnetic nanoparticles Thin film Pt nanoparticles [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat] 010306 general physics 0210 nano-technology ComputingMilieux_MISCELLANEOUS |
| Zdroj: | Journal of Magnetism and Magnetic Materials Journal of Magnetism and Magnetic Materials, Elsevier, 2007, 310 (2), pp.2417-2419. ⟨10.1016/j.jmmm.2006.10.806⟩ |
| ISSN: | 0304-8853 |
| DOI: | 10.1016/j.jmmm.2006.10.806⟩ |
| Popis: | Co–Pt and Co nanoparticles (∼2 nm diameter) of different composition and crystal structure have been studied by X-ray magnetic circular dichroism (XMCD) at the Co L 2,3 edges. The magnetic properties of the samples, covered with a thin protecting layer of Al 2 O 3 , depend upon the composition, order and presence of Co oxide contamination. Pure Co nanoparticles reveal an orbital-to-spin moment ratio, μ l / μ s =0.13 at room temperature (RT) and μ l / μ s =0.11 at 3.4 K, Co/Pt mixed nanoparticles show a temperature independent μ l / μ s ratio: 0.13 both at RT and at 3.4 K. In contrast, Pt-shell Co-core samples have a ratio μ l / μ s =0.14 at RT and a strongly enhanced ratio μ l / μ s =0.20 at 3.4 K. The same samples with a small CoO contamination show an enhanced μ l / μ ss =0.25 at RT and μ l / μ ss =0.28 at 3.4 K. In the reversed configuration (Pt-core and a Co-shell), where the CoO is probably not at the Co–Pt interface but at the Co surface, the enhancement of μ l / μ s caused by the simultaneous increases of the orbital moment and decreases of the spin moment reaches a record value of μ l / μ ss =0.33 at 3.4 K and μ l / μ ss =0.21 at RT. |
| Databáze: | OpenAIRE |
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