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arXiv · 1610.09000

Long-range exchange interaction between magnetic impurities in graphene

M. Agarwal·E. G. Mishchenko
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Abstract

The effective spin exchange coupling between impurities (adatoms) on graphene mediated by conduction electrons is studied as a function of the strength of the potential part of the on-site energy $U$ of the electron-adatom interaction. With increasing $U$, the exchange coupling becomes long-range, determined largely by the impurity levels with energies close to the Dirac points. When adatoms reside on opposite sublattices, their exchange coupling, normally antiferromagnetic, becomes ferromagnetic and resonantly enhanced at a specific distance where an impurity level crosses the Dirac point.

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M. Agarwal, E. G. Mishchenko. 2016-10-27. Long-range exchange interaction between magnetic impurities in graphene. https://doi.org/10.1103/physrevb.95.075411

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