Thermally and Molecularly Stimulated Relaxation of Hot Phonons in Suspended Carbon Nanotubes

TL;DR

This study explores how environmental factors like temperature and molecular coatings influence hot phonon relaxation in suspended carbon nanotubes, revealing pathways to improve high-current transport in nanoelectronics.

Contribution

It demonstrates that ambient temperature and molecular coatings significantly affect hot phonon relaxation, offering new insights into controlling high-bias transport in suspended nanotubes.

Findings

Higher ambient temperatures reduce non-equilibrium phonon effects.

Gas molecules facilitate hot phonon relaxation and increase current.

Frozen molecular solids can quench non-equilibrium phonons.

Abstract

The high-bias electrical transport properties of suspended metallic single-walled carbon nanotubes (SWNTs) are investigated at various temperatures in vacuum, in various gases and when coated with molecular solids. It is revealed that non-equilibrium optical phonon effects in suspended nanotubes decrease as the ambient temperature increases. Gas molecules surrounding suspended SWNTs assist the relaxation of hot phonons and afford enhanced current flow along nanotubes. Molecular solids of carbon dioxide frozen onto suspended SWNTs quench the non-equilibrium phonon effect. The discovery of strong environmental effects on high current transport in nanotubes is important to high performance nanoelectronics applications of 1D nanowires in general.