English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/131694
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:


High temperature magnetic stabilization of cobalt nanoparticles by an antiferromagnetic proximity effect

AuthorsToro, José A. de; Marques, Daniel P.; Muñiz, Pablo; Skumryev, Vassil; Sort, Jordi; Givord, Dominique; Nogués, Josep
Issue Date2015
PublisherAmerican Physical Society
CitationPhysical Review Letters 115(5):057201 (2015)
AbstractThermal activation tends to destroy the magnetic stability of small magnetic nanoparticles, with crucial implications for ultrahigh density recording among other applications. Here we demonstrate that low-blocking-temperature ferromagnetic (FM) Co nanoparticles (TB<70K) become magnetically stable above 400 K when embedded in a high-Néel-temperature antiferromagnetic (AFM) NiO matrix. The origin of this remarkable TB enhancement is due to a magnetic proximity effect between a thin CoO shell (with low Néel temperature, TN, and high anisotropy, KAFM) surrounding the Co nanoparticles and the NiO matrix (with high TN but low KAFM). This proximity effect yields an effective antiferromagnet with an apparent TN beyond that of bulk CoO, and an enhanced anisotropy compared to NiO. In turn, the Co core FM moment is stabilized against thermal fluctuations via core-shell exchange-bias coupling, leading to the observed TB increase. Mean-field calculations provide a semiquantitative understanding of this magnetic-proximity stabilization mechanism.
DescriptionUnder the terms of the Creative Commons Attribution License 3.0 (CC-BY).
Publisher version (URL)http://dx.doi.org/10.1103/PhysRevLett.115.057201
Identifiersdoi: 10.1103/PhysRevLett.115.057201
e-issn: 1079-7114
issn: 0031-9007
Appears in Collections:(CIN2) Artículos
Files in This Item:
File Description SizeFormat 
AntiferromagneticProximity.pdf287,46 kBAdobe PDFThumbnail
Show full item record
Review this work

Related articles:

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