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Fermi-level alignment at metal-carbon nanotube interfaces: application to scanning tunneling spectroscopy

Yongqiang Xue·Supriyo Datta
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Abstract

At any metal-carbon nanotube interface there is charge transfer and the induced interfacial field determines the position of the carbon nanotube band structure relative to the metal Fermi-level. In the case of a single-wall carbon nanotube (SWNT) supported on a gold substrate, we show that the charge transfers induce a local electrostatic potential perturbation which gives rise to the observed Fermi-level shift in scanning tunneling spectroscopy (STS) measurements. We also discuss the relevance of this study to recent experiments on carbon nanotube transistors and argue that the Fermi-level alignment will be different for carbon nanotube transistors with low resistance and high resistance contacts.

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Yongqiang Xue, Supriyo Datta. 1999-10-23. Fermi-level alignment at metal-carbon nanotube interfaces: application to scanning tunneling spectroscopy. https://doi.org/10.1103/physrevlett.83.4844

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