We report the electrical characteristics of two substrate-supported metallic single walled carbon nanotubes (SWNT) at temperatures up to 573 K over a range of bias voltages for zero gate voltage in air under atmospheric pressure. At low voltages or high ambient temperatures the observed electrical characteristics are most Ohmic. A theoretical formulation for resistance is used in a regression analysis to determine, from a global fit of all of the measurements, the room temperature optical and acoustic scattering lengths, and energy to emit optical phonons. The results show that the acoustic mean free path, which does not depend on voltage, is shortest at low ambient temperatures which leads to a linear relationship between current and voltage. At high ambient temperatures the acoustic, optical and absorption mean free paths converge independent of voltage, which again produces a linear variation of current that is consistent with the measurements.
Citation: Applied Physics Letters
Pub Type: Journals
carbon nanotubes, heat transfer, mean free path, phonons, resistance, temperature