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Negative Differential Conductance and Hot Phonons in Suspended Nanotube Molecular Wires

Eric Pop·David Mann·Jien Cao·Qian Wang·Kenneth Goodson·Hongjie Dai
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Abstract

Freely suspended metallic single-wall carbon nanotubes (SWNTs) exhibit reduced current carrying ability compared to those lying on substrates, and striking negative differential conductance (NDC) at low electric fields. Theoretical analysis reveals significant self-heating effects including electron scattering by hot non-equilibrium optical phonons. Electron transport characteristics under strong self-heating are exploited for the first time to probe the thermal conductivity of individual SWNTs (~ 3600 Wm-1K-1 at T=300 K) up to ~700 K, and reveal a 1/T dependence expected for Umklapp phonon scattering at high temperatures.

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Eric Pop, David Mann, Jien Cao, Qian Wang, Kenneth Goodson, Hongjie Dai. 2005-08-31. Negative Differential Conductance and Hot Phonons in Suspended Nanotube Molecular Wires. https://doi.org/10.1103/physrevlett.95.155505

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