Observation of Coulomb blockade in nanostructured epitaxial bilayer graphene on SiC
Journal article, 2017
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.
Author
C. Chua
University of Cambridge
Arseniy Lartsev
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Jinggao Sui
University of Cambridge
V. Panchal
National Physical Laboratory (NPL)
Reuben Puddy
University of Cambridge
Carly Richardson
University of Cambridge
Charles G. Smith
University of Cambridge
Tjbm Janssen
National Physical Laboratory (NPL)
Alexander Tzalenchuk
National Physical Laboratory (NPL)
Royal Holloway University of London
Rositza Yakimova
Linköping University
Sergey Kubatkin
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
M. Connolly
University of Cambridge
Carbon
0008-6223 (ISSN)
Vol. 119 426-430Subject Categories
Nano Technology
Condensed Matter Physics
DOI
10.1016/j.carbon.2017.04.019