Particle size dependence of exchange-bias and coercivity in CuO nanoparticles

被引：78

作者：

Seehra, MS

Punnoose, A ^{[1
]}

机构：

[1] Boise State Univ, Dept Phys, Boise, ID 83725 USA

[2] W Virginia Univ, Dept Phys, Morgantown, WV 26506 USA

来源：

SOLID STATE COMMUNICATIONS | 2003年 / 128卷 / 08期

基金：

美国国家科学基金会;

关键词：

insulators; magnetically ordered materials; chemical synthesis; exchange and superexchange;

D O I：

10.1016/j.ssc.2003.08.029

中图分类号：

O469 [凝聚态物理学];

学科分类号：

070205 ;

摘要：

For CuO nanocrystals of size 6.6-37 nm, the exchange bias H-eb and coercivity H-c are measured at 5 K in zero- field-cooled (ZFC) and field-cooled (FC at 50 kOe) samples and their variation,, investigated as a function of particle size D. The similar 1/D variations observed for the difference coercivity DeltaH(c) = H-c(FC) - H-c(ZFC) and the interfacial exchange energy Deltasigma = HebMfD are discussed in terms of the ferromagnetic magnetization M-f being produced by the uncompensated surface Cu2+ spins in the otherwise antiferromagnetically ordered CuO nanoparticles. This leads to the observation that the experimentally measured DeltaH(c) provides a good measure of Deltasigma in nanoparticle systems, with H-eb/DeltaH(c) varying as 1/MfD. (C) 2003 Elsevier Ltd. All rights reserved.

引用

页码：299 / 302

页数：4

共 18 条

[1] Dependence of exchange coupling on antiferromagnetic layer thickness in NiFe/CoO bilayers [J].