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arXiv · 1204.1101

Absence of broken inversion symmetry phase of electrons in bilayer graphene under charge density fluctuations

Xin-Zhong Yan·C. S. Ting
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Abstract

On a lattice model, we study the possibility of existence of gapped broken inversion symmetry phase (GBISP) of electrons with long-range Coulomb interaction in bilayer graphene using both self-consistent Hartree-Fock approximation (SCHFA) and the renormalized-ring-diagram approximation (RRDA). RRDA takes into account the charge-density fluctuations beyond the mean field. While GBISP at low temperature and low carrier concentration is predicted by SCHFA, we show here the state can be destroyed by the charge-density fluctuations. We also present a numerical algorithm for calculating the self-energy of electrons with the singular long-range Coulomb interaction on the lattice model.

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Xin-Zhong Yan, C. S. Ting. 2012-09-25. Absence of broken inversion symmetry phase of electrons in bilayer graphene under charge density fluctuations. https://doi.org/10.1103/physrevb.86.125438

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