Anomalous Magnetization Enhancement and Frustration in the Internal Magnetic Order on (Fe0.69Co0.31)B0.4 Nanoparticles

Applied Sciences

Belén Molina-Concha¹  Roberto D. Zysler¹ 

[1] Centro Atómico Bariloche, CNEA-CONICET, 8400 S.C. de Bariloche, RN, Argentina;

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

DOI  :  10.3390/app2020315

来源: mdpi

【 摘 要 】

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.

【 授权许可】

CC BY   
© 2012 by the authors; licensee MDPI, Basel, Switzerland.