  We have investigated theoretically the resonance splitting effect of Dirac
electrons through graphene superlattices with periodic potentials of square
barriers. It is found that each resonance peak in the transmission gap presents
(N-1)-fold resonance splitting for N-barriers, which is the analogy of the case
in semiconductor superlattices. The resonance splitting effect depends on the
incidence angle rather than the height and width of potential. However, there
is no explicit splitting rule for the conductance and shot noise, which is
different from the magnetic case. These properties may lead to potential
applications in graphene-based electron devices.
