Enhanced orbital magnetism in Fe50Pt50 nanoparticles

被引：138

作者：

Antoniak, C.

Lindner, J.

Spasova, M.

Sudfeld, D.

Acet, M.

Farle, M.

Fauth, K.

Wiedwald, U.

Boyen, H. -G.

Ziemann, P.

Wilhelm, F.

Rogalev, A.

Sun, Shouheng

机构：

[1] Univ Duisburg Gesamthsch, Fachbereich Phys, Expt AG Farle, D-47048 Duisburg, Germany

[2] Univ Wurzburg, D-97074 Wurzburg, Germany

[3] Max Planck Inst Met Res, D-70569 Stuttgart, Germany

[4] Univ Ulm, Abt Festkorperphys, D-89069 Ulm, Germany

[5] European Synchrotron Radiat Facil, F-38043 Grenoble, France

[6] Brown Univ, Dept Chem, Providence, RI 02912 USA

来源：

PHYSICAL REVIEW LETTERS | 2006年 / 97卷 / 11期

关键词：

D O I：

10.1103/PhysRevLett.97.117201

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

X-ray absorption and magnetic circular dichroism spectra at both the Fe and Pt L-3,L-2 edges were measured on wet-chemically synthesized monodisperse Fe50Pt50 particles with a mean diameter of 6.3 nm before and after complete removal of the organic ligands and the oxide shell covering the particles by soft hydrogen plasma resulting in a pure metallic state. After thermal treatment of the metallic particles, the coercive field increased by a factor of 6, the orbital magnetic moment at the Fe site increased by 330% and is reduced at the Pt site by 30%, while the effective spin moments did not change. A decrease of the frequency of oscillations in the extended x-ray absorption fine structure at the Pt L-3,L-2 edges provides evidence for crystallographic changes towards the L1(0) phase.

引用

页数：4

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