Graphene-based tortional resonator from molecular dynamics simulation

TL;DR

This study uses molecular dynamics simulations to analyze graphene-based torsional resonators, revealing how size and temperature affect their quality factor, which is crucial for designing future nano-mechanical devices.

Contribution

The paper introduces a detailed simulation-based analysis of the size and temperature dependence of the quality factor in graphene torsional resonators, highlighting boundary effects.

Findings

Quality factor depends on radius with a maximum at an optimal size.

Boundary effects significantly influence the resonator's behavior.

Quality factor exhibits a power-law temperature dependence with an exponent below 1.

Abstract

Molecular dynamics simulations are performed to study graphene-based torsional mechanical resonators. The quality factor is calculated by $Q_{F}=\omega\tau/2\pi$, where the frequency $\omega$ and life time $\tau$ are obtained from the correlation function of the normal mode coordinate. Our simulations reveal the radius-dependence of the quality factor as $Q_{F}=2628/(22R^{-1}+0.004R^{2})$, which yields a maximum value at some proper radius $R$. This maximum point is due to the strong boundary effect in the torsional resonator, as disclosed by the temperature distribution in the resonator. Resulting from the same boundary effect, the quality factor shows a power law temperature-dependence with power factors bellow 1.0. The theoretical results supply some valuable information for the manipulation of the quality factor in future experimental devices based on the torsional mechanical resonator.