Carrier Statistics and Quantum Capacitance of Graphene Sheets and Ribbons

In this work, fundamental results for carrier statistics in graphene 2-dimensional sheets and nanoscale ribbons are derived. Though the behavior of intrinsic carrier densities in 2d graphene sheets is found to differ drastically from traditional semiconductors, very narrow (sub-10 nm) ribbons are found to be similar to traditional narrow-gap semiconductors. The quantum capacitance, an important parameter in the electrostatic design of devices, is derived for both 2d graphene sheets and nanoribbons.