Interaction-induced insulating states in multilayer graphenes

Abstract

We explore the electronic ground states of Bernal-stacked multilayer graphenes using the Hartree-Fock mean-field approximation and the full-parameter band model. We find that the electron-electron interaction tends to open a band gap in multilayer graphenes from bilayer to 8-layer, while the nature of the insulating ground state sensitively depends on the band parameter ${\gamma }_2$, which is responsible for the semimetallic nature of graphite. In 4-layer graphene, particularly, the ground state assumes an odd-spatial-parity staggered phase at ${\gamma }_2=0$, while an increasing, finite value of ${\gamma }_2$ stabilizes a different state with even parity, where the electrons are attracted to the top layer and the bottom layer. The two phases are topologically distinct insulating states with different Chern numbers, and they can be distinguished by spin or valley Hall conductivity measurements. Multilayers with more than five layers also exhibit similar ground states with potential minima at the outermost layers, although the opening of a gap in the spectrum as a whole is generally more difficult than in 4-layer because of a larger number of energy bands overlapping at the Fermi energy.

8 pages, 6 figures

References in corpus (13)

• The electronic properties of bilayer graphene
• Electronic states and Landau levels in graphene stacks
• Transport in Bilayer Graphene: Calculations within a self-consistent Born approximation
• Orbital diamagnetism in multilayer graphenes: Systematic study with the effective mass approximation
• Pseudospin Magnetism in Graphene
• Magneto-optical properties of multilayer graphenes
• Quantum Anomalous Hall State in Bilayer Graphene
• Lattice Theory of Pseudospin Ferromagnetism in Bilayer Graphene: Competing Orders and Interaction Induced Quantum Hall States
• Minimum Conductivity and Evidence for Phase Transitions in Ultra-clean Bilayer Graphene
• Interacting fermions on the honeycomb bilayer: from weak to strong coupling
• Transport Gap in Suspended Bilayer Graphene at Zero Magnetic Field
• Insulating state in tetralayers reveals an even-odd interaction effect in multilayer graphene
• Interaction-induced insulating state in thick multilayer graphene

Cited by in corpus (1)

• Dimensional reduction, quantum Hall effect and layer parity in graphite films