Competing Ordered States in Bilayer Graphene

TL;DR

This paper uses a renormalization group approach to analyze competing ordered states in bilayer graphene, highlighting the influence of exchange, spin, and valley degeneracies on the emergence of gapped or gapless phases.

Contribution

It introduces a perturbative RG method to study the competition between different ordered states in bilayer graphene, emphasizing the role of flavor degeneracy and exchange effects.

Findings

Gapped states predicted for flavor numbers N=1,2,4

Susceptibility divergences indicate dominant ordered phases

Brief discussion on gapped states in ABC trilayer graphene

Abstract

We use a perturbative renormalization group approach with short-range continuum model interactions to analyze the competition between isotropic gapped and anisotropic gapless ordered states in bilayer graphene, commenting specifically on the role of exchange and on the importance of spin and valley flavor degeneracy. By comparing the divergences of the corresponding susceptibilities, we conclude that this approach predicts gapped states for flavor numbers N=1,2,4. We also comment briefly on the related gapped states expected in chiral (ABC) trilayer graphene.