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Electric Field-Dependent Charge-Carrier Velocity in Semiconducting Carbon Nanotubes

Yung-Fu Chen·M. S. Fuhrer
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Abstract

Charge transport in semiconducting single-walled nanotubes (SWNTs) with Schottky-barrier contacts has been studied at high bias. We observe nearly symmetric ambipolar transport with electron and hole currents significantly exceeding 25 micron-ampere, the reported current limit in metallic SWNTs due to optical phonon emission. Four simple models for the field-dependent velocity (ballistic, current saturation, velocity saturation, and constant mobility) are studied in the unipolar regime; the high-bias behavior is best explained by a velocity saturation model with a saturation velocity of 2 x 10^7 cm/s.

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Yung-Fu Chen, M. S. Fuhrer. 2005-10-07. Electric Field-Dependent Charge-Carrier Velocity in Semiconducting Carbon Nanotubes. https://doi.org/10.1103/physrevlett.95.236803

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