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Conductance enlargement in picoscale electroburnt graphene nanojunctions.

ABSTRACT: Provided the electrical properties of electroburnt graphene junctions can be understood and controlled, they have the potential to underpin the development of a wide range of future sub-10-nm electrical devices. We examine both theoretically and experimentally the electrical conductance of electroburnt graphene junctions at the last stages of nanogap formation. We account for the appearance of a counterintuitive increase in electrical conductance just before the gap forms. This is a manifestation of room-temperature quantum interference and arises from a combination of the semimetallic band structure of graphene and a cross-over from electrodes with multiple-path connectivity to single-path connectivity just before breaking. Therefore, our results suggest that conductance enlargement before junction rupture is a signal of the formation of electroburnt junctions, with a picoscale current path formed from a single sp(2) bond.

SUBMITTER: Sadeghi H

PROVIDER: S-EPMC4352825 | biostudies-other | 2015 Mar

REPOSITORIES: biostudies-other

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Conductance enlargement in picoscale electroburnt graphene nanojunctions.

Sadeghi Hatef H Mol Jan A JA Lau Chit Siong CS Briggs G Andrew D GA Warner Jamie J Lambert Colin J CJ

Proceedings of the National Academy of Sciences of the United States of America 20150217 9

Provided the electrical properties of electroburnt graphene junctions can be understood and controlled, they have the potential to underpin the development of a wide range of future sub-10-nm electrical devices. We examine both theoretically and experimentally the electrical conductance of electroburnt graphene junctions at the last stages of nanogap formation. We account for the appearance of a counterintuitive increase in electrical conductance just before the gap forms. This is a manifestatio ...[more]

PMID: 25730863

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