Control of Recoil Losses in Nanomechanical SiN Membrane Resonators

TL;DR

This paper presents a novel on-chip 'loss shield' structure for silicon nitride membrane resonators that significantly reduces recoil losses, achieving near-intrinsic quality factors across all modes and frequencies, suitable for advanced optomechanical applications.

Contribution

The authors designed and fabricated a loss shield structure that effectively suppresses recoil damping in SiN membrane resonators, maintaining high quality factors across modes.

Findings

Achieved a quality factor of 10^7 in the membrane resonator.

The loss shield reduces recoil damping to intrinsic silicon nitride dissipation levels.

Applicable at cryogenic temperatures for optomechanical systems.

Abstract

In the context of a recoil damping analysis, we have designed and produced a membrane resonator equipped with a specific on-chip structure working as a "loss shield" for a circular membrane. In this device the vibrations of the membrane, with a quality factor of $10^7$, reach the limit set by the intrinsic dissipation in silicon nitride, for all the modes and regardless of the modal shape, also at low frequency. Guided by our theoretical model of the loss shield, we describe the design rationale of the device, which can be used as effective replacement of commercial membrane resonators in advanced optomechanical setups, also at cryogenic temperatures.