Determining magnetic nanoparticle size distributions from thermomagnetic measurements

被引：28

作者：

DiPietro, R. S. ^{[1
]}

Johnson, H. G. ^{[1
]}

Bennett, S. P. ^{[2
]}

Nummy, T. J. ^{[1
]}

Lewis, L. H. ^{[3
]}

Heiman, D. ^{[1
]}

机构：

[1] Northeastern Univ, Dept Phys, Boston, MA 02115 USA

[2] Northeastern Univ, Dept Mech Engn, Boston, MA 02115 USA

[3] Northeastern Univ, Dept Chem Engn, Boston, MA 02115 USA

来源：

APPLIED PHYSICS LETTERS | 2010年 / 96卷 / 22期

基金：

美国国家科学基金会;

关键词：

antiferromagnetic materials; ferromagnetic materials; internal stresses; magnetic epitaxial layers; terbium compounds; MNAS; DEPENDENCE; SUSCEPTIBILITY; ANISOTROPY; GAAS(001); FILMS; GAAS; (GA;

D O I：

10.1063/1.3441411

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Thermomagnetic measurements are used to obtain the size distribution and anisotropy of magnetic nanoparticles. An analytical transformation method is described which utilizes temperature-dependent zero-field cooling magnetization data to provide a quantitative measurement of the average diameter and relative abundance of superparamagnetic nanoparticles. Applying this method to self-assembled MnAs nanoparticles in MnAs-GaAs composite films reveals a log-normal size distribution and reduced anisotropy for nanoparticles compared to bulk materials. This analytical technique holds promise for rapid assessment of the size distribution of an ensemble of superparamagnetic nanoparticles. (C) 2010 American Institute of Physics. [doi:10.1063/1.3441411]

引用

页数：3

共 26 条

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