Tunneling of Dirac fermions in graphene through a velocity barrier with modulated by magnetic fields

We study magnetic field modulated transport properties of Dirac fermions in graphene, where Dirac fermions penetrate through a velocity barrier. We find strong wave vector filtering and resonant effect. The angular-dependent region of resonant tunneling is suppressed by tuning velocity barriers. We can also found that the confined states in this velocity barrier can be changed by the magnetic field. Various novel devices, such as wavevector filter and magnetic switches, may be constructed based on our observed phenomena.