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Published on: July 24, 2015
Conductance fluctuations in graphene in the presence of long-range disorder
Bobo Liu1, Richard Akis1, David K Ferry1
1School of Electrical, Computer, and Energy Engineering, Arizona State University, Tempe, AZ 85287, USA.
Abstract:
The fluctuations in the conductance of graphene that arise from a long-range disorder potential induced by random impurities are investigated with an atomic tight-binding lattice. The screened impurities lead to a slow variation of the background potential and this varies the overall potential landscape as the Fermi energy or an applied magnetic field is varied. As a result, the phase interference varies randomly and leads to fluctuations in the conductance. Recently, experiments have shown that an applied magnetic field produces a remarkable reduction in the amplitude of these conductance fluctuations. We find qualitative agreement with these experiments, and it appears that the reduction in magnetic field of the fluctuations arises from a field induced smoothing of the conductance landscape.
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