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arXiv · 1203.0540

Crossover from Coulomb blockade to quantum Hall effect in suspended graphene nanoribbons

Dong-Keun Ki·Alberto F. Morpurgo
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Abstract

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 SiO$_2$ substrates.

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Dong-Keun Ki, Alberto F. Morpurgo. 2012-03-02. Crossover from Coulomb blockade to quantum Hall effect in suspended graphene nanoribbons. https://doi.org/10.1103/physrevlett.108.266601

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