Transport properties of Dirac electrons in graphene based double velocity-barrier structures in electric and magnetic fields

► We model graphene based velocity-barrier structures in electric and magnetic fields. ► Velocity barrier for ξ<1 (ξ>1) have property similar to electrostatic well (barrier). ► Velocity barrier for ξ>1 enlarge the resonant tunneling region of electrostatic barrier. ► The plateau width of Fano factor shortens (or broadens) for the case of ξ<1 (or ξ>1). ► The conductivity remains fixed at the point of EF=U0 for different values of ξ.