First-principles computation of surface segregation in L10 CoPt magnetic nanoparticles

被引：13

作者：

Liu, Zhenyu ^{[1
]}

Lei, Yinkai ^{[1
]}

Wang, Guofeng ^{[1
]}

机构：

[1] Univ Pittsburgh, Dept Mech Engn & Mat Sci, Pittsburgh, PA 15261 USA

来源：

JOURNAL OF PHYSICS-CONDENSED MATTER | 2016年 / 28卷 / 26期

基金：

美国国家科学基金会;

关键词：

surface segregation; magnetic nanoparticle; magnetic anisotropy energy; AUGMENTED-WAVE METHOD; ALLOY NANOPARTICLES; FEPT NANOPARTICLES; SIZE; ANISOTROPY; ENERGY; TRANSITION; PARTICLES; BEHAVIOR;

D O I：

10.1088/0953-8984/28/26/266002

中图分类号：

O469 [凝聚态物理学];

学科分类号：

070205 ;

摘要：

In this study, we have employed the first-principles density functional theory (DFT) computational method to predict the influence of surface segregation on the magnetic properties of small L1(0) CoPt nanoparticles. For both the modelled cuboidal (with a chemical formula of Co26Pt12) and cuboctahedral (with a chemical formula of Co18Pt20) CoPt nanoparticles, the DFT calculations predict that Pt surface segregation should occur thermodynamically. Associated with this Pt surface segregation, the surface-segregated CoPt magnetic nanoparticles are predicted to have significantly reduced magnetic moments and magnetic anisotropy energies than those of the corresponding bulk-terminated (i.e. non-segregated) nanoparticles. Hence, our study suggests that surface segregation could deteriorate the magnetic properties of CoPt nanoparticles.

引用

页数：10

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