Publication Date:
2015-10-13
Description:
Blocking temperatures of aggregates of Mn 0.5 Zn 0.5 Gd x Fe( 2- x )O 4 ferrite nanoparticles, with x = 0.02, 0.05, 0.11, 0.15, and 0.2, were obtained from the zero-field-cooled (ZFC) magnetization measurements. We found a nonmontonic behavior of the blocking temperature with increasing size of the particles. The effective magnetic anisotropy was calculated and found to have two distinct rates of increase with decreasing the size of the particles. These results were attributed to the strong inter-particle interactions in the aggregated nanoparticles and to the enhanced role of surface anisotropy with the decrease of the size of the particles. In three samples, the ZFC magnetization was found to exhibit a significant negative magnetization in a considerable part of the low temperature region. To our knowledge, this is the first time that negative magnetization is reported in such nanoparticles. These peculiar result...
Print ISSN:
1757-8981
Electronic ISSN:
1757-899X
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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