Transport Spectroscopy of Single-Walled Carbon Nanotubes

TL;DR

This study uses transport spectroscopy to analyze individual single-walled carbon nanotubes, revealing Zeeman splitting, electron parity effects, and possible double-dot behavior, advancing understanding of their quantum electronic properties.

Contribution

First detailed transport spectroscopy of single-walled carbon nanotubes showing Zeeman splitting and evidence of double-dot systems.

Findings

Zeeman splitting with g-factor of 2.04 ± 0.05

Electron parity influences peak splitting patterns

Signs of double-dot formation with anticrossing features

Abstract

We have performed transport spectroscopy on individual ropes of single-walled carbon nanotubes. We find that the levels are Zeeman split in a magnetic field, with a g-factor of 2.04 +- 0.05. The observed pattern of peak splittings indicates the parity of the number of electrons on the dot. In one device there are also signs of the presence of a second dot. We observe features which resemble anticrossings between quantum levels in the two dots, which may be formed from separate conducting nanotubes within the rope.