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arXiv · 1704.03757

A Hybrid-Monte-Carlo study of monolayer graphene with partially screened Coulomb interactions at finite spin density

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

We report on Hybrid-Monte-Carlo simulations at finite spin density of the $\pi$-band electrons in monolayer graphene with realistic inter-electron interactions. Unlike simulations at finite charge-carrier density, these are not affected by a fermion-sign problem. Our results are in qualitative agreement with an interaction-induced warping of the Fermi contours, and a reduction of the bandwidth as observed in angle resolved photoemission spectroscopy experiments on charge-doped graphene systems. Furthermore, we find evidence that the neck-disrupting Lifshitz transition, which occurs when the Fermi level traverses the van Hove singularity (VHS), becomes a true quantum phase transition due to interactions. This is in-line with an instability of the VHS towards the formation of electronic ordered phases, which has been predicted by a variety of different theoretical approaches.

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Michael Körner, Dominik Smith, Pavel Buividovich, Maksim Ulybyshev, Lorenz von Smekal. 2017-04-12. A Hybrid-Monte-Carlo study of monolayer graphene with partially screened Coulomb interactions at finite spin density. https://doi.org/10.1103/physrevb.96.195408

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