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arXiv · 1207.6478

Theoretical model of structure-dependent conductance crossover in disordered carbon

Mikhail V. Katkov·Somnath Bhattacharyya
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Abstract

We analyze the effects of sp^2/sp^3 bond-aspect ratio on the transport properties of amorphous carbon quasi-1D structures where structural disorder varies in a very non-linear manner with the effective bandgap. Using a tight-binding approach the calculated electron transmission showed a high probability over a wide region around the Fermi-level for sp^2-rich carbon and also distinct peaks close to the band edges for sp^3-rich carbon structures. This model shows a sharp rise of the structure resistance with the increase of sp^3C % followed by saturation in the wide bandgap regime for carbon superlattice-like structures and suggests the tuneable characteristic time of carbon-based devices.

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Mikhail V. Katkov, Somnath Bhattacharyya. 2012-07-27. Theoretical model of structure-dependent conductance crossover in disordered carbon. https://doi.org/10.1209/0295-5075%2F99%2F37005

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