2019/03/13 by Abderrahim El Mouhafid, Mouhafid, Abderrahim El, Ahmed Jellal +1
Materials Science · Physics and Astronomy · #FOS: Physical sciences #Graphene research and applications #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Quantum Physics (quant-ph) #Quantum and electron transport phenomena #Topological Materials and Phenomena #cond-mat.mes-hall #quant-ph
paper · pdf · doi:10.48550/arxiv.1903.05676
7 pages, 10 figures. arXiv admin note: text overlap with arXiv:1302.5623, arXiv:0906.4634, arXiv:1303.0533 by other authors
arxiv created 2019/03/13 · openalex publication_date 2019/03/13 · arxiv updated 2019/03/15 · openalex created_date 2022/07/29 · openalex updated_date 2026/07/28
We investigate the band structure of ABCA-tetralayer graphene (ABCA-TTLG) subjected to an external potential V applied between top and bottom layers. Using the tight-binding model, including the nearest t and next-nearest-neighbor t' hopping, low-energy model and two-band approximation model we study the band structure variation along the lines Γ-M-K-Γ in the first Brillouin zone, electronic band gap near Dirac point K and transmission properties, respectively. Our results reveal that ABCA-TTLG exhibits markedly different properties as functions of t' and V. We show that the hopping parameter t' changes the energy dispersion, the position of K and breaks sublattice symmetries. A sizable band gap is created at K, which could be opened and controlled by the applied potential V. This gives rise to 1D-like van Hove singularities (VHS) in the density of states (DOS). We study the relevance of the skew hopping parameters γ3 and γ4 to these properties and show that for energies E\gtrsim6meV their effects are negligible. Our results are numerically discussed and compared with the literature.