Negative Friction and Reversible Energy Exchange Between Orderly Motion and Phonons in Carbon Nanotube Oscillator

TL;DR

This study investigates energy exchange mechanisms between axial motion and phonons in carbon nanotube oscillators, revealing negative friction and reversible energy transfer, which could impact nanoscale device design.

Contribution

It introduces the concept of negative friction and demonstrates reversible energy exchange in carbon nanotube oscillators, a novel nanoscale tribological phenomenon.

Findings

Excess van der Waals energy is stored in low-frequency vibrational modes.

Energy exchange between motion and phonons can be reversible.

Negative friction observed in concentric carbon nanotube oscillators.

Abstract

Energy exchanges between orderly intertube axial motion and vibrational modes are studied for isolated systems of two coaxial carbon nanotubes at temperatures ranging from 300 K to 500 K. It is found that the excess intertube van der Waals energy, depleted from the intertube axial motion, is primarily stored in low-frequency mechanical modes of the oscillator for an extended period of time, and furthermore, such an energy exchange may be reversible. A new nanoscale tribological phenomenon of negative friction is reported for the first time in concentric cylindrical carbon nanotube oscillators.