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arXiv · 1104.5334

Spin-density-wave instability in graphene doped near the van Hove singularity

D. Makogon·R. van Gelderen·R. Roldán·C. Morais Smith
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Abstract

We study the instability of the metallic state towards the formation of a new ground state in graphene doped near the van Hove singularity. The system is described by the Hubbard model and a field theoretical approach is used to calculate the charge and spin susceptibility. We find that for repulsive interactions, within the random phase approximation, there is a competition between ferromagnetism and spin-density wave (SDW). It turns out that a SDW with a triangular geometry is more favorable when the Hubbard parameter is above the critical value U_c(T), which depends on the temperature T, even if there are small variations in the doping. Our results can be verified by ARPES or neutron scattering experiments in highly doped graphene.

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D. Makogon, R. van Gelderen, R. Roldán, C. Morais Smith. 2011-04-28. Spin-density-wave instability in graphene doped near the van Hove singularity. https://doi.org/10.1103/physrevb.84.125404

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