Observation of Coulomb blockade in nanostructured epitaxial bilayer graphene on SiC

Cassandra Chua; Arseniy Lartsev; Jinggao Sui; Vishal Panchal; Reuben Puddy; Carly Richardson; Charles G. Smith; T. J. B. M. Janssen; Alexander Tzalenchuk; Rositsa Yakimova; Sergey Kubatkin; Malcolm R. Connolly

arXiv · 1703.10848

Observation of Coulomb blockade in nanostructured epitaxial bilayer graphene on SiC

Cassandra Chua·Arseniy Lartsev·Jinggao Sui·Vishal Panchal·Reuben Puddy·Carly Richardson·Charles G. Smith·T. J. B. M. Janssen·Alexander Tzalenchuk·Rositsa Yakimova·Sergey Kubatkin·Malcolm R. Connolly

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Abstract

We study electron transport in nanostructures patterned in bilayer graphene patches grown epitaxially on SiC as a function of doping, magnetic field, and temperature. Away from charge neutrality transport is only weakly modulated by changes in carrier concentration induced by a local side-gate. At low n-type doping close to charge neutrality, electron transport resembles that in exfoliated graphene nanoribbons and is well described by tunnelling of single electrons through a network of Coulomb-blockaded islands. Under the influence of an external magnetic field, Coulomb blockade resonances fluctuate around an average energy and the gap shrinks as a function of magnetic field. At charge neutrality, however, conduction is less insensitive to external magnetic fields. In this regime we also observe a stronger suppression of the conductance below $T^*$, which we interpret as a sign of broken interlayer symmetry or strong fluctuations in the edge/potential disorder.

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Cassandra Chua, Arseniy Lartsev, Jinggao Sui, Vishal Panchal, Reuben Puddy, Carly Richardson, Charles G. Smith, T. J. B. M. Janssen, Alexander Tzalenchuk, Rositsa Yakimova, Sergey Kubatkin, Malcolm R. Connolly. 2017-03-31. Observation of Coulomb blockade in nanostructured epitaxial bilayer graphene on SiC. https://arxiv.org/abs/1703.10848

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