▎ 摘 要
Electronic band gap and transport in quasi-periodic graphene superlattice (GSL) of double-periodic sequence are investigated. It is found that such quasi-periodic structure can possess a zero-averaged wave-number (zero-(k) over bar) gap which is associated with an unusual Dirac point. Different from Bragg gap, the zero-(k) over bar gap is less sensitive to the incidence angle, and robust against the lattice constants. The locations of Dirac point and multi-Dirac-points in the GSLs of various sequences are also compared. The control of electron transport over the zero-(k) over bar band gap in GSLs may facilitate the development of many graphene-based electronics.