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arXiv · 1210.4741

Conductance of single-atom magnetic junctions: A first-principles study

Yi-qun Xie·Qiang Li·Lei Huang·Xiang Ye·San-Huang Ke
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Abstract

We present a first-principles investigation to show that the contact conductance of a half conductance quantum ($G_0/2$) found previously does not generally hold for single-atom magnetic junctions composed of a tip and an adatom dsorbed on a surface. The contact conductance of the Ni-Co/Co(111) junction is approximately $G_0/2$, while for the Co-Co/Co(111), Ni-Ni/Ni(111), and Ni-Ni/Ni(001) junctions the contact conductances are 0.80$G_0$, 1.55$G_0$, and 1.77$G_0$, respectively. The deviation from $G_0/2$ is mainly caused by the variation of the spin-down conductance largely determined by the minority $d$ orbitals, as the spin-up one changes little for different junctions.

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Yi-qun Xie, Qiang Li, Lei Huang, Xiang Ye, San-Huang Ke. 2012-10-17. Conductance of single-atom magnetic junctions: A first-principles study. https://doi.org/10.1063/1.4766733

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