Spin-glass-like behavior in CoO nanoparticles and the origin of exchange bias in layered CoO/Ferromagnet structures

被引：143

作者：

Gruyters, M ^{[1
]}

机构：

[1] Humboldt Univ, Inst Phys, D-12489 Berlin, Germany

来源：

PHYSICAL REVIEW LETTERS | 2005年 / 95卷 / 07期

关键词：

D O I：

10.1103/PhysRevLett.95.077204

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

The magnetic behavior of CoO nanoparticles and layered CoO/ferromagnetic (FM) structures has been investigated by magnetization and hysteresis loop measurements. In the amorphous CoO, a large uncompensation of spins is found that is closely related to spin-glass-like behavior below a freezing temperature T-F approximate to 215-220 K. The spin-glass-like phase may be described by the de Almeida-Thouless line for Ising spin systems. The exchange bias in the layered CoO/FM structures is explained by the spin-glass-like state in the nanoparticles constituting the CoO film.

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页数：4

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