Linear current fluctuations in the power-law region of metallic carbon nanotubes

TL;DR

This study investigates low frequency noise in metallic carbon nanotubes within their power-law conduction regime, revealing that relative noise remains bias-independent and decreases with optical phonon scattering, impacting nanoelectronic applications.

Contribution

It provides the first detailed analysis of current fluctuations in the power-law region of metallic nanotubes, linking noise behavior to optical phonon scattering effects.

Findings

Relative noise is bias-independent in the power-law regime.

Noise decreases significantly beyond the power-law regime due to optical phonon scattering.

Mobility fluctuations caused by phonons explain the noise reduction.

Abstract

We study low frequency noise in a non-Ohmic region of metallic single walled and multiwalled carbon nanotubes. The generalized relative noise appear to be independent of applied bias in the power-law regime of the tubes and in agreement with theoretical predictions. Beyond the power law regime the suppression of conductance due to scattering with optical phonons is accompanied by a reduction of relative noise by an order of magnitude. Mobility fluctuations in the tubes due to optical phonon scattering cause the unexpected reduction in the relative noise magnitude which is modeled using a modified mobility fluctuation picture. The findings have important implications for metallic nanotubes being used as interconnects in nanoelectronic devices.