High quality factor mg-scale silicon mechanical resonators for 3-mode optoacoustic parametric amplifiers

TL;DR

This paper reports the design and characterization of millimeter-scale silicon resonators with high quality factors suitable for 3-mode optoacoustic parametric amplification, advancing quantum measurement and signal transduction technologies.

Contribution

It introduces a novel silicon resonator design with minimized acoustic loss and high Q-factor at room temperature for 3-mode optoacoustic interactions.

Findings

Achieved a Q-factor of 7.5 x 10^5 at 401.5 kHz

Mode shape confirmed by mapping and finite element modeling

Resonators operate effectively at room temperature and low pressure

Abstract

Milligram-scale resonators have been shown to be suitable for the creation of 3-mode optoacoustic parametric amplifiers, based on a phenomena first predicted for advanced gravitational-wave detectors. To achieve practical optoacoustic parametric amplification, high quality factor resonators are required. We present millimetre-scale silicon resonators designed to exhibit a torsional vibration mode with a frequency in the 10^5 - 10^6 Hz range, for observation of 3-mode optoacoustic interactions in a compact table-top system. Our design incorporates an isolation stage and minimizes the acoustic loss from optical coating. We observe a quality factor of 7.5 x 10^5 for a mode frequency of 401.5 kHz, at room temperature and pressure of 10^-3 Pa. We confirmed the mode shape by mapping the amplitude response across the resonator and comparing to finite element modelling. This study contributes towards the development of 3-mode optoacoustic parametric amplifiers for use in novel high-sensitivity signal transducers and quantum measurement experiments.