Antiferromagnetism and competing charge instabilities of electrons in strained graphene from Coulomb interactions

Abstract

We study the quantum many-body ground states of electrons on the half-filled honeycomb lattice with short- and long-ranged density-density interactions as a model for graphene. To this end, we employ the recently developed truncated-unity functional renormalization group (TU-fRG) approach which allows for a high resolution of the interaction vertex' wavevector dependence. We connect to previous lattice quantum Monte Carlo (QMC) results which predict a stabilization of the semimetallic phase for realistic \emph{ab initio} interaction parameters and confirm that the application of a finite biaxial strain can induce a quantum phase transition towards an ordered ground state. In contrast to lattice QMC simulations, the TU-fRG is not limited in the choice of tight-binding and interaction parameters to avoid the occurrence of a sign problem. Therefore, we also investigate a range of parameters relevant to the realistic graphene material which are not accessible by numerically exact methods. Although a plethora of charge density waves arise under medium-range interactions, we find the antiferromagnetic spin-density wave to be the prevailing instability for long-range interactions. We further explore the impact of an extended tight-binding Hamiltonian with second-nearest neighbor hopping and a finite chemical potential for a more accurate description of the band structure of graphene's $p_z$ electrons.

17 pages, 12 figures

References in corpus (12)

• The electronic properties of graphene
• Exact evolution equation for the effective potential
• Dielectric function, screening, and plasmons in 2D graphene
• A tight-binding approach to uniaxial strain in graphene
• Topological Mott Insulators
• Interactions and phase transitions on graphene's honeycomb lattice
• Theory of interacting electrons on the honeycomb lattice
• Density waves and Cooper pairing on the honeycomb lattice
• How close can one approach the Dirac point in graphene experimentally?
• Charge instabilities and topological phases in the extended Hubbard model on the honeycomb lattice with enlarged unit cell
• Monte-Carlo simulation of the tight-binding model of graphene with partially screened Coulomb interactions
• Electronic structure of graphene hexagonal flake subjected to triaxial stress

Cited by in corpus (11)

• Reference results for the momentum space functional renormalization group
• TU${}^2$FRG -- a scalable approach for truncated unity functional renormalization group in generic fermionic models
• divERGe implements various Exact Renormalization Group examples
• Competition between d-wave superconductivity and magnetism in uniaxially strained Sr2RuO4
• Generalized dynamical mean-field theory of two-subalttice systems with non-local interactions and its application to study charge and spin correlations in graphene
• Consistent combination of truncated-unity functional renormalization group and mean-field theory
• Quantum spin Hall insulator on the honeycomb lattice induced by ferromagnetic exchange interaction
• Influence of hopping selfenergy and quasiparticle degradation on the antiferromagnetic ordering in the bilayer honeycomb Hubbard model
• Van-Hove tuning of Fermi surface instabilities through compensated metallicity
• Competing instabilities of the extended Hubbard model on the triangular lattice: Truncated-unity functional renormalization group and application to moiré materials
• Spin bond order driven by extended repulsive interactions in doped graphene