Amplitude calibration of 2D mechanical resonators by nonlinear optical transduction

TL;DR

This paper presents a contactless calibration method for 2D mechanical resonators using nonlinear optical transduction, enabling direct amplitude measurement without prior knowledge of device parameters.

Contribution

The authors introduce a novel calibration technique that detects higher harmonics from nonlinear optical signals to measure oscillation amplitudes of 2D resonators.

Findings

Calibration of resonance amplitude without device parameter assumptions

Detection of higher harmonics from nonlinear optical transduction

Applicable to atomically thin membrane resonators

Abstract

Contactless characterization of mechanical resonances using Fabry-Perot interferometry is a powerful tool to study the mechanical and dynamical properties of atomically thin membranes. However, amplitude calibration is often not performed, or only possible by making assumptions on the device parameters such as its mass or the temperature. In this work, we demonstrate a calibration technique that directly measures the oscillation amplitude by detecting higher harmonics that arise from nonlinearities in the optical transduction. Employing this technique, we calibrate the resonance amplitude of two-dimensional nanomechanical resonators, without requiring knowledge of their mechanical properties, actuation force, geometric distances or the laser intensity.