Frequency and Q-factor control of nanomechanical resonators

TL;DR

This paper introduces an integrated dielectric drive and read-out scheme for nanomechanical resonators, allowing voltage-controlled tuning of resonance frequency and quality factor, with design insights and experimental validation.

Contribution

It presents a model linking electric polarizability to frequency and Q-factor tuning, validated by experiments and FEM simulations, and demonstrates voltage control over these parameters.

Findings

Resonance frequency can be tuned by applied DC voltage.

Mechanical Q-factor can be reduced more than fivefold.

Electrode design influences tuning direction of modes.

Abstract

We present an integrated scheme for dielectric drive and read-out of high-Q nanomechanical resonators which enables tuning of both the resonance frequency and quality factor with an applied DC voltage. A simple model for altering these quantities is derived, incorporating the resonator's complex electric polarizability and position in an inhomogeneous electric field, which agrees very well with the experimental findings as well as FEM simulations. By comparing two sample geometries we are able to show that careful electrode design can determine the direction of frequency tuning of flexural in- and out-of-plane modes of a string resonator. Furthermore we demonstrate that the mechanical quality factor can be voltage reduced more than fivefold.