A Comparative Study of Integer Quantum Hall Effect in Monolayer and Bilayer Graphene

Graphene is the recently discovered two-dimensional (2D) nanomaterial. Electrons in graphene, obeying a linear dispersion relation, behave like massless relativistic particles. It has many peculiar properties. It is the thinnest material in the universe and the strongest ever measured. Its charge carriers exhibit intrinsic mobility and can travel micrometer-long distances without scattering at room temperature. Its unconventional Landau level spectrum of massless Dirac fermions leads to a new type of integer quantum Hall effect (IQHE). In monolayer graphene the first plateau occurs at 2e(2) / h and the generalised formula for the quantized Hall conductivity is sigma(xy) = 4e(2) / h (n + 1/2), where n is an integer. But in bilayer graphene the first plateau occurs at 4e(2) / h and the generalised formula for the quantized Hall conductivity is sigma(xy) =4ne(2) / h. In this paper, we comparatively study the IQHE in monolayer and bilayer graphene.