Structure and magnetic properties of Co nanoclusters fabricated by ion beam synthesis in SiO2 films

被引:21
作者
Klimenkov, M
von Borany, J
Matz, W
Eckert, D
Wolf, M
Müller, KH
机构
[1] Rossendorf Inc, Forschungszentrum Rossendorf EV, Inst Ion Beam Phys & Mat Res, D-01314 Dresden, Germany
[2] Zent Inst Festkorperphys & Werkstofforsch, D-01171 Dresden, Germany
来源
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING | 2002年 / 74卷 / 04期
关键词
D O I
10.1007/s003390100915
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Co nanoparticles fabricated by ion beam synthesis in SiO2 films were investigated with transmission electron microscopy and superconducting quantum interference device technique. Variation of the thermal treatment enables the formation of Co nanoclusters of different sizes ranging from 2 to 40 nm. Small nanoclusters of about 2-3 nm are amorphous, whereas clusters above 7 nm show the configuration of cubic Co nanocrystals. Measurements of magnetisation at temperatures between 2 K and 360 K reveal superparamagnetic behaviour for the small nanoclusters up to 3 nm and ferromagnetism for clusters above 7 nm.
引用
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页码:571 / 575
页数:5
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