English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/19242
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:

DC FieldValueLanguage
dc.contributor.authorBartolomé, Juan-
dc.contributor.authorBartolomé, Fernando-
dc.contributor.authorGarcía, L. M.-
dc.contributor.authorLuis, Fernando-
dc.identifier.citationSmart Materials for Ranging Systems 226: 1-25 (2006)en_US
dc.description25 pages, 16 figures, 1 table.-- et al.en_US
dc.description.abstractThe present work deals with the observation of enhancement of the magnetic anisotropy of Co nanoparticles and its origin. The samples were granular multilayer samples prepared by sequential deposition, by sputtering, of amorphous Al2O3 and Co layers on a Si substrate. Co nanoparticles are selforganized in a quasi-regular spatial order of approximately hexagonal closepacked symmetry. The particles studied range in average diameter 〈D〉 between 0.7 nm and nearly 5 nm, with a narrow size distribution. This well controlled morphology has enabled us to circumvent ambiguities in sample configuration and, by means of a simple model for fluctuating moments, explain the dynamics of the Co particle moments in terms of an activation energy with contributions from anisotropy Keff, dipole-dipole interactions Edip, and a bias magnetic field H. The anisotropy is enhanced by one to two orders of magnitude with respect to the bulk fcc Co due to strong pinning of the surface Co magnetic moments anisotropy, and increase as 1/D as the particle diameter decreases. The origin of this enhancement is related to an increase of the orbital magnetic moment at the surface atoms. Capping the Co nanospheres with a Cu film increases further the particle anisotropy and the orbital magnetic moment of the surface atoms.en_US
dc.description.sponsorshipWe are grateful to D. Babonneau, J. Carrey and J.L. Maurice for the GIXAXS and TEM experiments and many fruitful discussions. The early magnetic measurements of J.M. Torres-Bruna and J. Stanckiewicz are also acknowledged. This work has been financed by the MAT03/166 MCYT project. We acknowledge the European Synchrotron Radiation Facility for provision of synchrotron radiation facilities and we would like to thank Peter Bencok and Nick Brookes for assistance in using beamline ID08."en_US
dc.format.extent10752 bytes-
dc.titleMagnetic dynamics of Co Nanospheres: origin of the enhanced anisotropy.en_US
dc.description.peerreviewedPeer revieweden_US
Appears in Collections:(ICMA) Artículos
Files in This Item:
File Description SizeFormat 
accesoRestringido.pdf15,38 kBAdobe PDFThumbnail
Show simple item record

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.