Conductance enlargement in picoscale electroburnt graphene nanojunctions.
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.
Physics Department, Quantum Technology Centre, Lancaster University, LA1 4YB Lancaster, United Kingdom; and h.sadeghi@lancaster.ac.uk c.lambert@lancaster.ac.uk.
Hatef
H
Sadeghi
Department of Materials, University of Oxford, Oxford OX1 3PH, United Kingdom.
Jan A
JA
Mol
Department of Materials, University of Oxford, Oxford OX1 3PH, United Kingdom.
Chit Siong
CS
Lau
Department of Materials, University of Oxford, Oxford OX1 3PH, United Kingdom.
G Andrew D
GA
Briggs
Department of Materials, University of Oxford, Oxford OX1 3PH, United Kingdom.
Jamie
J
Warner
Physics Department, Quantum Technology Centre, Lancaster University, LA1 4YB Lancaster, United Kingdom; and h.sadeghi@lancaster.ac.uk c.lambert@lancaster.ac.uk.
Colin J
CJ
Lambert
electroburning; graphene; nanoelectronics; picoelectronics; quantum interference