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Coupled dynamics of electrons and phonons in metallic nanotubes: current saturation from hot phonons generation

Michele Lazzeri·Francesco Mauri
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Abstract

We show that the self-consistent dynamics of both phonons and electrons is the necessary ingredient for the reliable description of the hot phonons generation during electron transport in metallic single-wall carbon nanotubes (SWNTs). We solve the coupled Boltzmann transport equations to determine in a consistent way the current vs. voltage (IV) curve and the phonon occupation in metallic SWNTs which are lying on a substrate. We find a good agreement with measured IV curves and we determine an optical phonon occupation which corresponds to an effective temperature of several thousands K (hot phonons), for the voltages typically used in experiments. We show that the high-bias resistivity strongly depends on the optical phonon thermalization time. This implies that a drastic improvement of metallic nanotubes performances can be achieved by increasing the coupling of the optical phonons with a thermalization source.

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Michele Lazzeri, Francesco Mauri. 2006-03-02. Coupled dynamics of electrons and phonons in metallic nanotubes: current saturation from hot phonons generation. https://doi.org/10.1103/physrevb.73.165419

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