Shell-driven magnetic stability in core-shell nanoparticles

被引：202

作者：

Nogues, J. ^{[1
]}

Skumryev, V.

Sort, J.

Stoyanov, S.

Givord, D.

机构：

[1] Univ Autonoma Barcelona, ICREA, E-08193 Barcelona, Spain

[2] Univ Autonoma Barcelona, Dept Fis, E-08193 Barcelona, Spain

[3] Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA

[4] CNRS, Lab Louis Neel, F-38042 Grenoble 9, France

来源：

PHYSICAL REVIEW LETTERS | 2006年 / 97卷 / 15期

关键词：

D O I：

10.1103/PhysRevLett.97.157203

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

The magnetic properties of ferromagnetic-antiferromagnetic Co-CoO core-shell nanoparticles are investigated as a function of the in-plane coverage density from 3.5% to 15%. The superparamagnetic blocking temperature, the coercivity, and the bias field radically increase with increasing coverage. This behavior cannot be attributed to the overall interactions between cores. Rather, it can be semiquantitatively understood by assuming that the shells of isolated core-shell nanoparticles have strongly degraded magnetic properties, which are rapidly recovered as nanoparticles come into contact.

引用

页数：4

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