ABSTRACT
This chapter investigates electronic properties and optical excitations in the geometry- and electric-field-modulated bilayer graphene systems, respectively, by using the tight-binding model and gradient approximation. The modulation of stacking configuration will lead to a great enlargement of the unit cell. The magneto-electronic properties, energy spectrum, density of states, and wave functions, directly link one another by the competitive/cooperative pictures. The oscillatory Landau subbands are predicted to come to exist under the nonuniform environment, being thoroughly different from the dispersionless Landau levels in the well-stacked graphene systems. The high-resolution angle-resolved photoemission spectroscopy is the only experimental instrument able to directly examine the wave-vector-dependent occupied electronic states. The nonuniform intralayer and interlayer hopping integrals have dramatically changed the main features of magnetic wave functions; that is, Landau subbands are quite different from Landau levels in the spatial distributions.
