High quality mechanical and optical properties of commercial silicon nitride membranes

TL;DR

This study demonstrates that commercial silicon nitride membranes possess exceptionally high mechanical quality factors and low optical losses, making them ideal for quantum optomechanics research.

Contribution

It provides detailed measurements showing commercial silicon nitride membranes have superior mechanical and optical properties compared to similar devices.

Findings

Mechanical Q > 10^6 at room temperature

Mechanical Q > 10^7 at 300 mK

Optical loss less than 2E-4 at near-IR

Abstract

We have measured the optical and mechanical loss of commercial silicon nitride membranes. We find that 50 nm-thick, 1 mm^2 membranes have mechanical Q > 10^6 at 293 K, and Q > 10^7 at 300 mK, well above what has been observed in devices with comparable dimensions. The near-IR optical loss at 293 K is less than 2E-4. This combination of properties make these membranes attractive candidates for studying quantum effects in optomechanical systems.