Fermi velocity renormalization in misoriented graphene on hexagonal boron nitride

The electronic structure, Fermi velocity, and bandgap are calculated for graphene on BN as a function of misorientation angle. The Fermi velocity of Bernal stacked graphene on BN increases to 1.6 $v_0$ where $v_0$ is the velocity of single-layer graphene. For misorientation angles ranging from 5 to 27 degrees, the Fermi velocities of the Dirac electrons in graphene are relatively insensitive to the angle with values ranging between 0.85 and 0.9 $v_0$. In addition, the bandgap at the Dirac point for rotated graphene on BN decreases by an order of magnitude compared to that of perfectly registered graphene on h-BN. This suggests a reduction in the interlayer coupling between the graphene and BN layers due to the rotation. Calculations are performed using density functional theory.