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arXiv · 0904.2651

Point-Contact Conductance in Asymmetric Chalker-Coddington Network Model

Koji Kobayashi·Tomi Ohtsuki·Keith Slevin
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Abstract

We study the transport properties of disordered two-dimensional electron systems with a perfectly conducting channel. We introduce an asymmetric Chalker-Coddington network model and numerically investigate the point-contact conductance. We find that the behavior of the conductance in this model is completely different from that in the symmetric model. Even in the limit of a large distance between the contacts, we find a broad distribution of conductance and a non-trivial power law dependence of the averaged conductance on the system width. Our results are applicable to systems such as zigzag graphene nano-ribbons where the numbers of left-going and right-going channels are different.

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Koji Kobayashi, Tomi Ohtsuki, Keith Slevin. 2009-07-27. Point-Contact Conductance in Asymmetric Chalker-Coddington Network Model. https://doi.org/10.1143/jpsj.78.084708

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