Four-point resistance of individual single-wall carbon nanotubes

TL;DR

This study investigates the electrical resistance of individual single-wall carbon nanotubes using four-point measurements, revealing classical behavior at room temperature and quantum effects at cryogenic temperatures.

Contribution

It provides the first detailed analysis of four-point resistance in single-wall carbon nanotubes, highlighting temperature-dependent quantum interference effects.

Findings

Resistance is linear with length at room temperature

Quantum interference causes negative resistance at cryogenic temperatures

Interface resistance influences four-point measurements

Abstract

We have studied the resistance of single-wall carbon nanotubes measured in a four-point configuration with noninvasive voltage electrodes. The voltage drop is detected using multiwalled carbon nanotubes while the current is injected through nanofabricated Au electrodes. The resistance at room temperature is shown to be linear with the length as expected for a classical resistor. This changes at cryogenic temperature; the four-point resistance then depends on the resistance at the Au-tube interfaces and can even become negative due to quantum-interference effects.