Strain-dependent damping in nanomechanical resonators from thin $\mathrm{MoS_2}$ crystals

TL;DR

This study explores how mechanical strain affects damping and resonance in MoS2 nanomechanical resonators, revealing strain-dependent damping behavior influenced by geometric imperfections like wrinkles.

Contribution

It demonstrates the strain-dependent damping effects in MoS2 nanodrums and highlights the role of geometric imperfections in dissipation mechanisms.

Findings

Resonance linewidth varies significantly with strain in flat devices.

Buckled devices show less pronounced strain effects and hysteresis.

Microscopic wrinkles may contribute to energy dissipation in 2D material resonators.

Abstract

We investigate the effect of mechanical strain on the dynamics of thin $\mathrm{MoS_2}$ nanodrum resonators. Using a piezoelectric crystal, compressive and tensile biaxial strain is induced in initially flat and buckled devices. In the flat device, we observe a remarkable strain-dependence of the resonance line width, while the change in the resonance frequency is relatively small. In the buckled device, the strain-dependence of the damping is less pronounced, and a clear hysteresis is observed. The experiment suggests that geometric imperfections, such as microscopic wrinkles, could play a role in the strong dissipation observed in nanoresonators fabricated from 2-D materials.