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arXiv · 1405.2152

Spin Spirals in Surface Alloys on Ru(0001): A First-principles Study

Sananda Biswas·Gustav Bihlmayer·Shobhana Narasimhan·Stefan Blügel
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Abstract

We have used ab initio density functional theory to compute the magnetic ground states of the surface alloy systems FeAu$_2$/Ru(0001) and MnAu$_2$/Ru(0001). For both systems, we find that the lowest energy magnetic configuration corresponds to a left-rotating spin spiral, in which the sense of rotation is determined by the Dzyaloshinskii-Moriya interaction. These spirals are lower in energy than the ferromagnetic configuration by 3-4 meV per nm$^2$. We also find that FeAu$_2$/Ru(0001) has a significantly high magnetic anisotropy energy, of the order 1 meV per Fe atom. By comparing with the corresponding freestanding alloy monolayers, we find that the presence of the Ru substrate plays a significant role in determining the magnetic properties of the surface alloy systems.

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Sananda Biswas, Gustav Bihlmayer, Shobhana Narasimhan, Stefan Blügel. 2014-05-09. Spin Spirals in Surface Alloys on Ru(0001): A First-principles Study. https://arxiv.org/abs/1405.2152

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