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Metal-Semiconductor Transition in Armchair Carbon Nanotubes by Symmetry Breaking

Yan Li·Slava V. Rotkin·Umberto Ravaioli
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Abstract

The electronic band structure of armchair carbon nanotubes may be considerably modified by potentials with angular dependence. Different angular modes V_q ~ cos(q*theta) have been studied within a tight-binding scheme. Using symmetry arguments, we demonstrate a bandgap opening in these metallic nanotubes when certain selection rules are satisfied for both potential and nanotube structure. We estimate the bandgap opening as a function of both the external potential strength and the nanotube radius and suggest an effective mechanism of metal-semiconductor transition by combination of different forms of perturbations.

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Yan Li, Slava V. Rotkin, Umberto Ravaioli. 2005-11-16. Metal-Semiconductor Transition in Armchair Carbon Nanotubes by Symmetry Breaking. https://doi.org/10.1063/1.1811792

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