2020/11/28 by Niels R. Walet, F. Guinea, Francisco Guinea · 1 citation
Chemistry · Materials Science · Mathematics · Physics and Astronomy · #Antiparallel (mathematics) #Boron and Carbon Nanomaterials Research #Chemistry #Condensed matter physics #Crystallography #Diamond and Carbon-based Materials Research #Geometry #Graphene research and applications #Lattice (music) #Materials science #Mathematics #Physics #Quantum mechanics #Twist #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.103.125427
published as Phys. Rev. B 103, 125427 (2021)
arxiv created 2020/11/28 · openalex created_date 2020/12/07 · openalex publication_date 2021/03/25 · arxiv updated 2021/03/31 · openalex updated_date 2026/08/05
We study the effect of twisting on bilayer h\text\ensuremath-BN. The effect of lattice relaxation is included; we look at the electronic structure, piezoelectric charges, and spontaneous polarization. We show that the electronic structure without lattice relaxation shows a set of extremely flat in-gap states similar to Landau levels, where the spacing scales with twist angle. With lattice relaxation we still have flat bands, but now the spectrum becomes independent of twist angle for sufficiently small angles. We describe in detail the nature of the bands and we study appropriate continuum models, at the same time explaining the structure of the in-gap states. We find that even though the spectra for both parallel and antiparallel alignment are very similar, the spontaneous polarization effects only occur for parallel alignment. We argue that this suggests a large interlayer hopping between boron and nitrogen.