Transport Properties of Carbon Nanotube C$_{60}$ Peapods

TL;DR

This study investigates the electrical conductance of carbon nanotube peapods across a wide temperature range, revealing minimal impact of encapsulated C$_{60}$ molecules on electron backscattering near the Fermi level, despite known modifications away from it.

Contribution

It provides the first comprehensive conductance measurements of nanotube peapods from room temperature to millikelvin temperatures, highlighting the minimal backscattering effect of C$_{60}$ molecules.

Findings

Devices show metallic and semiconducting behavior at room temperature.

Single electron effects observed at millikelvin temperatures.

Encapsulated C$_{60}$ molecules do not cause significant backscattering near the Fermi level.

Abstract

We measure the conductance of carbon nanotube peapods from room temperature down to 250mK. Our devices show both metallic and semiconducting behavior at room temperature. At the lowest temperatures, we observe single electron effects. Our results suggest that the encapsulated C$_{60}$ molecules do not introduce substantial backscattering for electrons near the Fermi level. This is remarkable given that previous tunneling spectroscopy measurements show that encapsulated C$_{60}$ strongly modifies the electronic structure of a nanotube away from the Fermi level.