Evidence for semiconducting behavior with a narrow band gap of Bernal graphite
arXiv:1106.0437 · doi:10.1088/1367-2630/14/5/053015
Abstract
We have studied the resistivity of a large number of highly oriented graphite samples with areas ranging from several mm$^2$ to a few $μ$m$^2$ and thickness from $\sim 10 $nm to several tens of micrometers. The measured resistance can be explained by the parallel contribution of semiconducting graphene layers with low carrier density $< 10^9$ cm$^{-2}$ and the one from metallic-like internal interfaces. The results indicate that ideal graphite with Bernal stacking structure is a narrow-gap semiconductor with an energy gap $E_g \sim 40 $meV.
14 pages, 4 Figures, to be published in New Journal of Physics (in press, 2012)