Magnetism in exposed and coated nanoclusters studied by dichroism in X-ray absorption and photoemission

被引：14

作者：

Binns, C ^{[1
]}

Baker, SH

Edmonds, KW

Finetti, P

Maher, MJ

Louch, SC

Dhesi, SS

Brookes, NB

机构：

[1] Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England

[2] Univ Nottingham, Sch Phys & Astron, Nottingham NG7 2RD, England

[3] INFM, Lab TASC, Palazzina MM, I-34012 Basovizza, Italy

[4] ESRF, F-38043 Grenoble, France

来源：

PHYSICA B-CONDENSED MATTER | 2002年 / 318卷 / 04期

关键词：

nanoclusters; dichroism; nanomagnetism;

D O I：

10.1016/S0921-4526(02)00804-9

中图分类号：

O469 [凝聚态物理学];

学科分类号：

070205 ;

摘要：

We have studied the evolution of the magnetic behaviour of size-selected Fe nanoclusters from isolated particles adsorbed on a surface exposed in UHV to dense interacting assemblies. The Clusters were produced by a UHV-compatible gas aggregation source and were studied in situ by synchrotron radiation techniques based on dichroism. Isolated and exposed Fe clusters deposited on highly oriented pyrolitic graphite Substrates exhibit orbital and spin magnetic moments that are, respectively, tip to 250% and 10% higher than the values measured in thick Fe films. The moments decay towards the bulk value with increasing cluster size or with increasing particle density on the surface. The total moment in the supported clusters is not as high as observed in free clusters of the same size. The individual particles appear to be magnetically isotropic but a strong in-plane coherent anisotropy develops as the coverage is increased to a complete cluster monolayer. Coating the deposited Fe clusters with a Co film substantially increases the spin moment on the Fe. (C) 2002 Elsevier Science B.V. All rights reserved.

引用

页码：350 / 359

页数：10

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