1998/05/15 by Tsuneya Ando, Takeshi Nakanishi · 11 citations
Materials Science · #Graphene research and applications #Carbon Nanotubes in Composites #Thermal properties of materials
paper · doi:10.1143/jpsj.67.1704
The effective potential of an impurity in a k · p scheme is derived in two-dimensional graphite sheet. When the potential range is smaller than the lattice constant, it has an off-diagonal matrix element between K and K ′ points comparable to the diagonal element. With the increase of the range, this off-diagonal element decreases rapidly and the diagonal element for envelopes at A and B sites becomes identical. The crossover between these two regimes occurs around the range smaller than the lattice constant. In the latter regime, back scattering between states with + k and - k vanishes identically for the bands crossing the Fermi level in the absence of a magnetic field, leading to an extremely large conductivity. The absence of the back scattering disappears in magnetic fields, giving rise to a huge positive magnetoresistance.