Long-lived discrete breathers in free-standing graphene

TL;DR

This study uses molecular dynamics simulations to explore long-lived discrete breathers in free-standing graphene, revealing their potential observability in experiments due to extended lifetimes at high temperatures.

Contribution

It demonstrates that realistic molecular dynamics simulations predict significantly longer breather lifetimes in graphene than previously thought, highlighting their experimental relevance.

Findings

Breather lifetimes reach hundreds of picoseconds at high temperatures.

Lifetimes depend on the interatomic potential used.

Discrete breathers could be observed via Raman spectroscopy.

Abstract

Intrinsic localized modes or discrete breathers are investigated by molecular dynamics simulations in free-standing graphene. Discrete breathers are generated either through thermal quenching of the graphene lattice or by proper initialization, with frequencies and lifetimes sensitively depending on the interatomic potential describing the carbon-carbon interaction. In the most realistic scenario, for which temperature-dependent molecular dynamics simulations in three dimension using a graphene-specific interatomic potential are performed, the breather lifetimes increase to hundreds of picoseconds even at relatively high temperatures. These lifetimes are much higher than those anticipated from earlier calculations, and may enable direct breather observation in Raman spectroscopy experiments.