• Submit to Applied Sciences Login Register
• MDPI
• Journals A-Z
• For Authors
• For Editors
• About
• Open Access Policy

• Abstract
• Full-Text PDF [396 KB]
• Full-Text XML
• Article Versions Notes

• Article Statistics
• Google Scholar
• Order Reprints

• Cite this article
• Export to BibTeX
• Export to EndNote

• [+] on DOAJ
• Molina-Concha, B
• Zysler, R
• Romero, H
• [+] on Google Scholar
• Molina-Concha, B
• Zysler, R
• Romero, H
• [+] on PubMed
• Molina-Concha, B
• Zysler, R
• Romero, H

•  CiteULike
•  Facebook
•  Mendeley
•  Twitter

This article is

• freely available
• re-usable

Appl. Sci. 2012, 2(2), 315-326; doi:10.3390/app2020315

Article

Anomalous Magnetization Enhancement and Frustration in the Internal Magnetic Order on (Fe_0.69Co_0.31)B_0.4 Nanoparticles

Belén Molina-Concha ^1,† , Roberto D. Zysler ^1,*  and Héctor Romero ²

¹ Centro Atómico Bariloche, CNEA-CONICET, 8400 S.C. de Bariloche, RN, Argentina ² Facultad de Ciencias, Departamento de Física, Universidad de Los Andes, Mérida, 5101, Venezuela ^† Present address: Intitut National de l’Energie Solaire-Commissariat à l’Energie Atomique, 50 avenue du lac Léman, 73375 Le Bourget du Lac, France.

* Author to whom correspondence should be addressed.

Received: 14 February 2012; in revised form: 19 March 2012 / Accepted: 23 March 2012 / Published: 2 April 2012

(This article belongs to the Special Issue Magnetic Nanoparticles: Synthesis, Properties and Applications)

Download PDF Full-Text [396 KB, uploaded 10 April 2012 16:55 CEST]

Abstract: We have studied the internal magnetic order of 3-nm (Fe_0.69Co_0.31)_0.6B_0.4 amorphous nanoparticles. These nanoparticles were dispersed in a non-magnetic matrix (non-interacting nanoparticles) to contrast them with the powder samples, where strong interparticle interactions are present. In similar fashion to the bulk alloy, this system exhibits a saturation magnetization maximum as a function of Fe composition near 69 at% Fe for the powder and dispersed samples at all temperatures. The saturation magnetization (M_S) of the dispersed sample shows anomalous behavior, revealing frustration in the internal magnetic order of the particles. Unexpectedly, the M_S of the non-interacting sample at low temperatures is larger than the corresponding bulk alloy or the calculated value of M_S for the same Fe-Co composition. By contrast, the powder sample has low M_S values and it is approximately constant in temperature.

Keywords: fine-particle systems; amorphous magnetic materials; Fe-Co-B alloys; magnetic anisotropy; magnetization enhancement

Article Statistics

Cite This Article