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Zero-Conductance Resonances due to Flux States in Nanographite Ribbon Junctions

Katsunori Wakabayashi·Manfred Sigrist
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Abstract

The electronic transport properties through junctions in nanographite ribbons are investigated using the Landauer approach. In the low-energy regime ribbons with zigzag boundary have a single conducting channel of edge states. The conductance as a function of the chemical potential shows a rich structure with sharp dips of zero conductance. Each zero-conductance resonance is connected with a resonant state which can be interpreted as the superposition of two degenerate flux states with Kekulé-like current patterns. These zero-conductance dips are connected with a pronounced negative magneto resistance.

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BibTeXRIS

Katsunori Wakabayashi, Manfred Sigrist. 1999-12-21. Zero-Conductance Resonances due to Flux States in Nanographite Ribbon Junctions. https://doi.org/10.1103/physrevlett.84.3390

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