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Pt steps decorated by 3d nanowires calculated via an order-N method

Sam Shallcross·Igor Abrikosov·Velimir Meded
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Abstract

We present the magnetization energy and magnetic moments of 3d monowires aligned along the step edges of Pt (533) and (322) vicinal substrates. We employ an electronic structure method which scales linearly with the size of the system. This allows us to treat with ease both ferromagnetic and antiferromagnetic solutions, and in principle the method should allow for the evaluation of more complex systems, such as wires deposited on rough step edges. We find that Co, Fe, and Mn are almost perfect Heisenberg systems, with almost no change in the moment between antiferromagnetic and ferromagnetic solutions. A large polarisation of the Pt substrate is also observed. Our results are in close agreement w ith recent experimental results obtained for the case of a Co monowire. As expected the trend is for the late d series to be stabalised by ferromagnetic long range order and the middle of the d series by antiferromagnetic order. Since our method is only \emph{locally} self consistent we discuss as some length the convergence of the results with respect to the size of the region which is treated self-consistently.

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Sam Shallcross, Igor Abrikosov, Velimir Meded. 2005-02-11. Pt steps decorated by 3d nanowires calculated via an order-N method. https://arxiv.org/abs/cond-mat/0502295

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