In this thesis, we consider the electronic properties of materials created by stacking
two-dimensional graphene layers. The first material is a heterostructure created
by placing a graphene layer on top of a layer of hexagonal boron nitride. The
energy bands are determined as well as the energy spectrum in the presence of
a magnetic field applied in the direction perpendicular to the layers. There is a
miniband structure that includes gaps and secondary Dirac points as well as a
fractal structure of magnetic minibands known as Hofstadter's butterfly. The second material is multilayer graphene, which consists of a small number
of graphene layers stacked on top of one another. We determine the effect on the
low-energy electronic band structure by applying a magnetic field in the direction
parallel to the layers, and find that the parallel field can induce a dramatic
change in the band structure, which is known as a Lifshitz transition. Furthermore,
depending on the magnitude and the direction of the field within the plane
of the graphene layers, it is possible to access different phase regions of the band
structure. We also model the electronic transport properties of multilayer graphene. We
use both analytical mode-matching and the numerical recursive Green function
methods to study the transport properties of electrons in multilayer graphene in
the vicinity of zero energy, zero temperature and zero magnetic field.