%0 Journal Article
%T Anomalous Magnetization Enhancement and Frustration in the Internal Magnetic Order on (Fe0.69Co0.31)B0.4 Nanoparticles
%A Bel¨Śn Molina-Concha
%A Roberto D. Zysler
%A H¨Śctor Romero
%J Applied Sciences
%D 2012
%I MDPI AG
%R 10.3390/app2020315
%X 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 ( MS) of the dispersed sample shows anomalous behavior, revealing frustration in the internal magnetic order of the particles. Unexpectedly, the MS of the non-interacting sample at low temperatures is larger than the corresponding bulk alloy or the calculated value of MS for the same Fe-Co composition. By contrast, the powder sample has low MS values and it is approximately constant in temperature.
%K fine-particle systems
%K amorphous magnetic materials
%K Fe-Co-B alloys
%K magnetic anisotropy
%K magnetization enhancement
%U http://www.mdpi.com/2076-3417/2/2/315