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Numerical study of the lattice vacancy effects on the single-channel electron transport of graphite ribbons

Katsunori Wakabayashi
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Abstract

Lattice vacancy effects on electrical conductance of nanographite ribbon are investigated by means of the Landauer approach using a tight binding model. In the low-energy regime ribbons with zigzag boundary provide a single conducting channel whose origin is connected with the presence of edge states. It is found that the chemical potential dependence of conductance strongly depends on the difference ($Δ$) of the number of removed A and B sublattice sites. The large lattice vacancy with $Δ\neq 0$ shows $2Δ$ zero-conductance dips in the single-channel region, however, the large lattice vacancy with $Δ=0$ has no dip structure in this region. The connection between this conductance rule and the Longuet-Higgins conjecture is also discussed.

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Katsunori Wakabayashi. 2002-10-31. Numerical study of the lattice vacancy effects on the single-channel electron transport of graphite ribbons. https://doi.org/10.1143/jpsj.71.2500

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