Magnetic properties and microstructure of isolated Fe-Pt nanoparticle-monolayer assembly by protective coating

被引：8

作者：

Chen, MP ^{[1
]}

Kuroishi, K ^{[1
]}

Kitamoto, Y ^{[1
]}

机构：

[1] Tokyo Inst Technol, Dept Innovat & Engn Mat, Yokohama, Kanagawa 2268502, Japan

来源：

IEEE TRANSACTIONS ON MAGNETICS | 2005年 / 41卷 / 10期

基金：

日本学术振兴会;

关键词：

carbon; Fe-Pt; hafnium oxide; magnetocrystalline anisotropy; nanoparticle-monolayer; overcoat; RECORDING MEDIA;

D O I：

10.1109/TMAG.2005.855350

中图分类号：

TM [电工技术]; TN [电子技术、通信技术];

学科分类号：

0808 ; 0809 ;

摘要：

In order to diminish coalescence and interparticle sintering during high-temperature annealing of Fe-Pt nanoparticle films above 700 K, carbon or hafnium oxide overcoats are deposited on the nanoparticle-monolayer films. TEM observations reveal that grains in the Fe-Pt nanoparticle-monolayers are kept to be 4 mn in size even after annealing at 873 K; the particle size is close to the crystallite size estimated using Scherrer's formula as 4 nm from x-ray diffraction. In-plane coercivity of the monolayer films at room temperature is 4 kOe and much higher than that without any overcoats. Furthermore, the hafnium-oxide coated monolayer-film shows a high magnetocrystalline anisotropy (K-u = 4 x 10(7) erg/cm(3)) and a high Ku V/kT value of 39.2 at 300 K, indicating the, Fe-Pt nanoparticle-monolayers have high thermal stability as magnetic recording media.

引用

页码：3376 / 3378

页数：3

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