Magnetic superlattice and finite-energy Dirac points in graphene

This is the authors' abstract. We don't add key points for this paper.

We study the band structure of graphene's Dirac-Weyl quasiparticles in a one-dimensional magnetic superlattice formed by a periodic sequence of alternating magnetic barriers. The spectrum and the nature of the states strongly depend on the conserved longitudinal momentum and on the barrier width. At the center of the superlattice Brillouin zone we find new Dirac points at finite energies where the dispersion is highly anisotropic, in contrast to the dispersion close to the neutrality point which remains isotropic. This finding suggests the possibility of collimating Dirac-Weyl quasiparticles by tuning the doping.