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arXiv · 1509.06427

Proximity induced quantum anomalous Hall effect in graphene/EuO hetero-structures

Shanshan Su·Yafis Barlas·Roger K. Lake
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Abstract

In a heterostructure of graphene and the ferromagnetic insulator EuO, the Eu atoms induce proximity exchange and inter-valley interactions in the graphene layer. Constrained by the lattice symmetries, and guided by ab initio calculations, a model Hamiltonian is constructed that describes the low-energy bands. Band parameters such as proximity induced exchange splitting, spin orbit coupling, and inter-valley interaction are determined. Calculations of the Chern number identify the conditions under which the hetero-structures exhibit topologically non-trivial bands that give rise to the quantum anomalous Hall effect with a Hall conductivity of $σ_{xy} = 2 e^2/h$.

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Shanshan Su, Yafis Barlas, Roger K. Lake. 2015-09-21. Proximity induced quantum anomalous Hall effect in graphene/EuO hetero-structures. https://doi.org/10.1103/physrevb.95.075418

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