▎ 摘　　要

We investigate the band structure and the tunneling of ABCA-tetralayer graphene (ABCA-TTLG) subjected to an external potential U-0 applied between top and bottom layers. Using the tight-binding model, including the nearest.. and next-nearest-neighbor t' hopping, low-energy model and two-band approximation model we study the band structure variation along the lines Gamma - M - K - Gamma in the first Brillouin zone, electronic band gap near Dirac point K, transmission properties and conductance, respectively. Our results reveal that ABCA-TTLG exhibits markedly different properties as functions of t' and U-0. 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 U-0. This gives rise to 1D-like van Hove singularities (VHS) in the density of states (DOS). Resonant electronic transmission through graphene-based a pnp junction is studied as a function of the incident wave vector, the width and height of the barrier with and without U-0. The resonant features in the transmission result from resonant hole states in the barrier and strongly influence the conductance. Our results are numerically discussed and compared with the literature.