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arXiv · 1811.00865

Noncollinear spin density of an adatom on a magnetic surface

Soumyajyoti Haldar·Stefan Heinze
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Abstract

We show that an individual adatom on a magnetic surface can exhibit a noncollinear spin density. Using density functional theory we study Co and Ir adatoms on a Mn monolayer on the W(110) surface which possesses a noncollinear canted spin structure. Due to hybridization with the nearest and next-nearest Mn atoms of the monolayer the spin direction of the underlying substrate is encoded into the orbitals of the adatom. This explains recent scanning tunneling microscopy experiments showing a spin sensitive shape asymmetry of adatoms [Serrate \emph{et al.}, Phys. Rev. B \textbf{93}, 125424 (2016)] which confirms the intra-atomic noncollinear magnetism of the adatoms.

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Soumyajyoti Haldar, Stefan Heinze. 2018-11-02. Noncollinear spin density of an adatom on a magnetic surface. https://doi.org/10.1103/physrevb.98.220401

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