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arXiv · 0911.3004

Exchange coupling in transition-metal nano-clusters on Cu(001) and Cu(111) surfaces

Phivos Mavropoulos·Samir Lounis·Stefan Blügel
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Abstract

We present results of density-functional calculations on the magnetic properties of Cr, Mn, Fe and Co nano-clusters (1 to 9 atoms large) supported on Cu(001) and Cu(111). The inter-atomic exchange coupling is found to depend on competing mechanisms, namely ferromagnetic double exchange and antiferromagnetic kinetic exchange. Hybridization-induced broadening of the resonances is shown to be important for the coupling strength. The cluster shape is found to weaken the coupling via a mechanism that comprises the different orientation of the atomic d-orbitals and the strength of nearest-neighbour hopping. Especially in Fe clusters, a correlation of binding energy and exchange coupling is also revealed.

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Phivos Mavropoulos, Samir Lounis, Stefan Blügel. 2009-11-16. Exchange coupling in transition-metal nano-clusters on Cu(001) and Cu(111) surfaces. https://doi.org/10.1002/pssb.200945535

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