2018/12/31 by Thierry Jolicoeur, Csaba Tőke, Inti Sodemann
Chemistry · Materials Science · Physics and Astronomy · #Bilayer #Bilayer graphene #Carbon Nanotubes in Composites #Chemistry #Condensed matter physics #Degenerate energy levels #Dielectric #Electron #Ferroelectricity #Graphene #Graphene research and applications #Ground state #Landau quantization #Materials science #Physics #Quantum Hall effect #Quantum and electron transport phenomena #Quantum mechanics #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.99.115139
published as Phys. Rev. B 99, 115139 (2019) · 15 pages, 13 figures
arxiv created 2019/03/29 · openalex publication_date 2019/03/29 · arxiv updated 2019/04/03 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We reexamine the nature of the ground states of bilayer graphene at odd integer filling factors within a simplified model of nearly degenerate n=0 and n=1 Landau levels. Previous Hartree-Fock studies have found that ferroelectric states with orbital coherence can be stabilized by tuning the orbital splitting between these levels. These studies indicated that, in addition to a uniform ferroelectric state, a helical ferroelectric phase with spontaneously broken translational symmetry is possible. By performing exact diagonalization on the torus, we argue that the system does not have a uniform coherent state but instead transitions directly from the uniform incoherent state into the ferroelectric helical phase. We argue that there is a realistic prospect to stabilize the helical ferroelectric state in bilayer graphene by tuning the interlayer electric field in a model that includes all single-particle corrections to its zero energy eightfold multiplet of Landau levels.