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arXiv · 1901.03490

Tunability of Magnetic Anisotropy of Co on Two-Dimensional Materials by Tetrahedral Bonding

D. Odkhuu·T. Tsevelmaa·P. Taivansaikhan·N. Park·S. C. Hong·S. H. Rhim
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Abstract

Pairing of $\pi$ electronic state structures with functional or metallic atoms makes them possible to engineer physical and chemical properties. Herein, we predict the reorientation of magnetization of Co on hexagonal BN (h-BN) and graphene multilayers. The driving mechanism is the formation of the tetrahedral bonding between sp$^3$ and d orbitals at the interface. More specifically, the intrinsic $\pi$-bonding of h-BN and graphene is transformed to sp$^3$ as a result of strong hybridization with metallic $d_{z^2}$ orbital. The different features of these two tetrahedral bondings, sp$^2$ and sp$^3$, are well manifested in charge density and density of states in the vicinity of the interface, along with associated band structure near the $\bar{K}$ valley. Our findings provide a novel approach to tailoring magnetism by means of degree of the interlayer hybrid bonds in 2D layered materials.

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D. Odkhuu, T. Tsevelmaa, P. Taivansaikhan, N. Park, S. C. Hong, S. H. Rhim. 2019-01-11. Tunability of Magnetic Anisotropy of Co on Two-Dimensional Materials by Tetrahedral Bonding. https://doi.org/10.1103/physrevb.99.014419

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