High quality factor mechanical resonance in a silicon nanowire

TL;DR

This study demonstrates high-quality factor silicon nanowire resonators at millikelvin temperatures, confirming theoretical predictions and highlighting their potential for ultra-sensitive mass sensing applications.

Contribution

The paper reports the fabrication and experimental characterization of silicon nanowire resonators with high quality factors at very low temperatures, aligning with Euler-Bernoulli theory predictions.

Findings

Resonance frequencies match Euler-Bernoulli estimates.

Achieved internal quality factor of 3.62×10^4 at 20 mK.

Potential mass sensitivity of approximately 6×10^{-20} g/Hz^{1/2}.

Abstract

Resonance properties of nanomechanical resonators based on doubly clamped silicon nanowires, fabricated from silicon-on-insulator and coated with a thin layer of aluminum, were experimentally investigated. Resonance frequencies of the fundamental mode were measured at a temperature of $20\,\mathrm{mK}$ for nanowires of various sizes using the magnetomotive scheme. The measured values of the resonance frequency agree with the estimates obtained from the Euler-Bernoulli theory. The measured internal quality factor of the $5\,\mathrm{\mu m}$-long resonator, $3.62\times10^4$, exceeds the corresponding values of similar resonators investigated at higher temperatures. The structures presented can be used as mass sensors with an expected sensitivity $\sim 6 \times 10^{-20}\,\mathrm{g}\,\mathrm{Hz}^{-1/2}$.