Moment fluctuations in 7 nm γ-Fe2O3 nanoparticles probed at the atomic level using Mossbauer spectroscopy

被引：15

作者：

Desautels, R. D. ^{[1
]}

Skoropata, E. ^{[1
]}

van Lieropa, J. ^{[1
]}

机构：

[1] Univ Manitoba, Dept Phys & Astron, Winnipeg, MB R3T 2N2, Canada

来源：

JOURNAL OF APPLIED PHYSICS | 2008年 / 103卷 / 07期

关键词：

D O I：

10.1063/1.2830963

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

We have examined the local magnetism of 7 nm gamma-Fe2O3 nanoparticles as a function of temperature using transmission Mossbauer spectroscopy. Spectra indicate that the nanoparticles exhibit two different spin populations: one is due to the core Fe moments, while the other is from the surface moments. We find that the uniaxial anisotropy of the core increases with temperature from 5 to 75 K, whereupon it remains constant. Simultaneously, the surface moment fluctuations increase in frequency with warming.

引用

页数：3

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