Suspended graphene nano-ribbons formed during current annealing of suspended graphene flakes have been investigated experimentally. Transport measurements show the opening of a transport gap around charge neutrality due to the formation of "Coulomb islands", coexisting with quantum Hall conductance plateaus appearing at moderate values of magnetic field B. Upon increasing B, the transport gap is rapidly suppressed, and is taken over by a much larger energy gap due to electronic correlations. Our observations show that suspended nano-ribbons allow the investigation of phenomena that could not so far be accessed in ribbons on SiO2 substrates.
@article{arxiv.1203.0540,
title = {Crossover from Coulomb blockade to quantum Hall effect in suspended graphene nanoribbons},
author = {Dong-Keun Ki and Alberto F. Morpurgo},
journal= {arXiv preprint arXiv:1203.0540},
year = {2015}
}
Comments
5 pages and 5 figures, Accepted in Physical Review Letters