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arXiv · 0705.0786

Peculiar Band Gap Structure of Graphene Nanoribbons

Motohiko Ezawa
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Abstract

Graphene nanoribbons are quasi-one-dimensional meterials with finite width. Characterizing a wide class of nanoribbons by edge shape and width, we make a systematic analysis of their electronic properties. The band gap structure of nanoribbons is shown to exhibit a valley structure with stream-like sequences of metallic or almost metallic nanoribbons. Among them, all zigzag nanoribbons are metallic, and armchair nanoribbons are metallic by period of 3. We find that these stream-like sequences correspond to equi-width curves, and that the band gap of chiral and armchair nanoribbons oscillate as a function of the width. Furthermore a possible application of nanoribbons to nanoelectronics is discussed.

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Motohiko Ezawa. 2007-05-06. Peculiar Band Gap Structure of Graphene Nanoribbons. https://doi.org/10.1002/pssc.200790003%2010.1002%2Fpssc.200673205

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