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Local pressure-induced metallization of a semiconducting carbon nanotube in a crossed junction

L. Vitali·M. Burghard·P. Wahl·M. A. Schneider·K. Kern
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Abstract

The electronic and vibrational density of states of a semiconducting carbon nanotube in a crossed junction was investigated by elastic and inelastic scanning tunneling spectroscopy. The strong radial compression of the nanotube at the junction induces local metallization spatially confined to a few nm. The local electronic modifications are correlated with the observed changes in the radial breathing and G-band phonon modes, which react very sensitively to local mechanical deformation. In addition, the experiments reveal the crucial contribution of the image charges to the contact potential at nanotube-metal interfaces.

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L. Vitali, M. Burghard, P. Wahl, M. A. Schneider, K. Kern. 2005-05-23. Local pressure-induced metallization of a semiconducting carbon nanotube in a crossed junction. https://doi.org/10.1103/physrevlett.96.086804

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