Nonlinear parametric amplification in a tri-port nanoelectromechanical device

TL;DR

This paper demonstrates a highly sensitive, electrically driven nonlinear parametric amplification technique in nanoelectromechanical systems, achieving force detection at the femtonewton scale and amplifying small forces over 100 times.

Contribution

It introduces a novel electrical method for nonlinear parametric amplification in NEMS, with theoretical modeling and practical applications including damping measurements.

Findings

Force detection sensitivity down to femtonewtons

Force amplification exceeding 100 times

Measurement of anelastic damping with 0.5% resolution

Abstract

We report on measurements performed at low temperatures on a nanoelectromechanical system (NEMS) under (capacitive) parametric pumping. The excitations and detection schemes are purely electrical, and enable in the present experiment the straightforward measurement of forces down to about a femtonewton, for displacements of an Angstr\"om, using standard room temperature electronics. We demonstrate that a small (linear) force applied on the device can be amplified up to more than a 100 times, while the system is {\it truly moving}. We explore the dynamics up to about 50$~$nm deflections for cantilevers about 200$~$nm thick by 3$~$$\mu$m long oscillating at a frequency of 7$~$MHz. We present a generic modeling of nonlinear parametric amplification, and give analytic theoretical solutions enabling the fit of experimental results. We finally discuss the practical limits of the technique, with a particular application: the measurement of {\it anelastic damping} in the metallic coating of the device with an exceptional resolution of about 0.5$~$\%.