Intrinsic Energy Dissipation in CVD-Grown Graphene Nanoresonators

TL;DR

This study uses molecular dynamics to analyze how intrinsic grain boundaries in CVD-grown graphene affect nanoresonator Q-factors, revealing that defects significantly reduce energy quality but can be mitigated by tensile strain.

Contribution

It provides the first detailed analysis of intrinsic grain boundary effects on graphene nanoresonator Q-factors and shows strain can improve performance.

Findings

Q-factors are 10-100 times lower with grain boundaries.

Symmetry and structure of defect pairs influence Q-factors.

Modest tensile strain can significantly improve Q-factors.

Abstract

We utilize classical molecular dynamics to study the the quality (Q)-factors of monolayer CVD-grown graphene nanoresonators. In particular, we focus on the effects of intrinsic grain boundaries of different orientations, which result from the CVD growth process, on the Q-factors. For a range of misorientations orientation angles that are consistent with those seen experimentally in CVD-grown graphene, i.e. 0$^{\circ}$ to $\sim20^{\circ}$, we find that the Q-factors for graphene with intrinsic grain boundaries are 1-2 orders of magnitude smaller than that of pristine monolayer graphene. We find that the Q-factor degradation is strongly influenced by both the symmetry and structure of the 5-7 defect pairs that occur at the grain boundary. Because of this, we also demonstrate that find the Q-factors CVD-grown graphene can be significantly elevated, and approach that of pristine graphene, through application of modest (1%) tensile strain.