Spin splitting and even-odd effects in carbon nanotubes

TL;DR

This paper investigates the spin splitting and even-odd effects in the electronic spectrum of carbon nanotubes, revealing how magnetic fields and electron addition influence their quantum states and transport properties.

Contribution

It provides experimental evidence of spin and even-odd effects in carbon nanotubes using transport spectroscopy, highlighting the influence of magnetic fields on their energy levels.

Findings

Zeeman splitting observed in magnetic fields parallel to nanotubes

Ground state spin alternates by 1/2 with electron addition

Coulomb blockade characteristics exhibit even-odd effects

Abstract

The level spectrum of a single-walled carbon nanotube rope, studied by transport spectroscopy, shows Zeeman splitting in a magnetic field parallel to the tube axis. The pattern of splittings implies that the spin of the ground state alternates by 1/2 as consecutive electrons are added. Other aspects of the Coulomb blockade characteristics, including the current-voltage traces and peak heights, also show corresponding even-odd effects.