Doped single‐walled carbon nanotubes and low‐mobility graphene: impact of disorder and dopants on electronic magnetotransport

The impact of disorder introduced by intentional and unintentional (environmental) dopants on the charge transport has been investigated in boron‐ and nitrogen‐doped single‐walled carbon nanotubes, and in low‐mobility monolayer graphene. For doped single‐walled nanotubes a theoretically not predicted plateau‐like region and onsets of oscillatory behaviour in the conductance for boron‐ and nitrogen‐doped nanotubes were observed, respectively. The oscillatory behaviour suggests interplay between the dopants and the helical movement of charges along the tube due to the magnetic field. For low‐mobility graphene the simultaneous appearance of the filling‐factor 2 and 3 plateau was observed in the Quantum‐Hall regime. This is attributed to an electron‐spin–isospin interaction mediated through the high disorder. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)