Improved optomechanical disk resonator sitting on a pedestal mechanical shield

TL;DR

This paper demonstrates a method to significantly enhance the mechanical quality factor of GaAs disk optomechanical resonators using a pedestal mechanical shield, with potential for very high Q values.

Contribution

The study introduces a novel pedestal shield design that improves Q factors in GaAs disk resonators, supported by experimental results and numerical modeling.

Findings

Q improved by a factor of 10 to 16 with the shield

Mode analysis reveals the Q enhancement mechanism

Optimized double-disk geometry predicts Q above one million

Abstract

We experimentally demonstrate the controlled enhancement of the mechanical quality factor Q of GaAs disk optomechanical resonators. Disks vibrating at 1.3 GHz with a mechanical shield integrated in their pedestal show a Q improvement by a factor 10 to 16. The structure is modeled numerically and different modes of vibration are observed, which shed light on the Q enhancement mechanism. An optimized double-disk geometry is presented that promises Q above the million for a large parameter range.