Low-frequency Current Fluctuations in Individual Semiconducting Single-Wall Carbon Nanotubes

TL;DR

This study investigates low-frequency 1/f noise in individual semiconducting carbon nanotubes, revealing that noise levels are linked to the number of transport carriers and comparable to bulk semiconductors, aiding nanostructure characterization.

Contribution

It provides a systematic analysis of 1/f noise in single nanotubes, establishing the relationship between noise and carrier number, and offers a new method for characterizing low-dimensional nanostructures.

Findings

1/f noise level correlates with the number of transport carriers.

Noise per carrier is comparable to bulk semiconductors.

Small carrier numbers cause pronounced noise in nanotubes.

Abstract

We present a systematic study on low-frequency current fluctuations of nano-devices consisting of one single semiconducting nanotube, which exhibit significant 1/f-type noise. By examining devices with different switching mechanisms, carrier types (electrons vs. holes), and channel lengths, we show that the 1/f fluctuation level in semiconducting nanotubes is correlated to the total number of transport carriers present in the system. However, the 1/f noise level per carrier is not larger than that of most bulk conventional semiconductors, e.g. Si. The pronounced noise level observed in nanotube devices simply reflects on the small number of carriers involved in transport. These results not only provide the basis to quantify the noise behavior in a one-dimensional transport system, but also suggest a valuable way to characterize low-dimensional nanostructures based on the 1/f fluctuation phenomenon.