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arXiv · 1703.05743

Inter-electron interactions and the RKKY potential between H adatoms in graphene

Pavel Buividovich·Dominik Smith·Maksim Ulybyshev·Lorenz von Smekal
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Abstract

We use first-principles Quantum Monte-Carlo simulations to study the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction between hydrogen adatoms attached to a graphene sheet. We find that the pairwise RKKY interactions at distances of a few lattice spacings are strongly affected by inter-electron interactions, in particular, the potential barrier between widely separated adatoms and the dimer configuration becomes wider and thus harder to penetrate. We also point out that anti-ferrromagnetic and charge density wave orderings have very different effects on the RKKY interaction. Finally, we analyze the stability of several regular adatom superlattices with respect to small displacements of a single adatom, distinguishing the cases of adatoms which populate either both or only one sublattice of the graphene lattice.

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Pavel Buividovich, Dominik Smith, Maksim Ulybyshev, Lorenz von Smekal. 2017-03-16. Inter-electron interactions and the RKKY potential between H adatoms in graphene. https://doi.org/10.1103/physrevb.96.165411

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