Dimensionality effects on magnetic properties of FexCo1-x nanoclusters on Pt(111)

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:441

Article

Miranda, I. P.¹  Igarashi, R. N.²  Klautau, A. B.³  Petrilli, H. M.¹ 

[1] Univ Sao Paulo, Inst Fis, CEP 66318, BR-05315970 Sao Paulo, SP, Brazil

[2] Univ Anhembi Morumbi, Escola Engn & Tecnol, BR-04546002 Sao Paulo, SP, Brazil

[3] Univ Fed Para, Fac Fis, BR-66075110 Belem, Para, Brazil

关键词: Nanomagnetism;    Electronic structure;    Dimensionality effects;    Local magnetic moments;    Iron and cobalt on platinum;   

DOI  :  10.1016/j.jmmm.2017.05.059

来源: Elsevier

【 摘 要 】

The behavior of local magnetic moments and exchange coupling parameters of FexCo1-x nanostructures (nanowires and compact clusters) on the fcc Pt(1 1 1) surface is here investigated using the first-principles real-space RS-LMTO-ASA method, in the framework of the DFT. Different configurations of FexCo1-x trimers and heptamers on Pt(1 1 1) are considered, varying the positions and the concentration of Fe or Co atoms. We discuss the influence of dimensionality and stoichiometry changes on the magnetic properties, specially on the orbital moments, which are very important in establishing a nanoscopic understanding of delocalized electron systems. We demonstrate the existence of a strictly decreasing nonlinear trend of the average orbital moments with the Fe concentration for the compact clusters, different from what was found for FexCo1-x nanowires on Pt(1 1 1) and also for corresponding higher-dimensional systems (FexCo1-x monolayer on Pt(1 1 1) and FexCo1-x bulk). The average spin moments, however, are invariably described by a linear function with respect to stoichiometry. In all studied cases, the nearest neighbors exchange couplings have shown to be strongly ferromagnetic. (C) 2017 Elsevier B.V. All rights reserved.

【 授权许可】

Free