ECAMP 15

Optomechanical platforms with high-quality mechanical and optical resonators have a wide application potential ranging from quantum limited sensing to long-lived storage of quantum information. Whilst exceptionally high-quality factors have been realized with structures in thin layers of dielectric or semiconducting materials, their geometries are limited by the capacity of lithographic fabrication. Recent developments in polymer-based 3D direct laser-written structures allow for new paradigms in manufacturing micromechanical resonators, but so far suffer from strong mechanical dissipation.
Here, we showcase our recent progress on implementing and improving this platform. The losses impacting the mechanical Q-factor of the resonator in vacuum are dominated by intrinsic losses within the material such as friction and thermoelastic damping. These losses, however, can be heavily reduced by introducing strain on the membrane, leading to so-called dissipation dilution. This is done by adjusting the fabrication process and engineering the geometry of the resonator for optimized aspect ratios.
To quantify the results of our methods a scannable vacuum-integrated fiber cavity setup for probing high quality-factor mechanical resonators is used. We present the impact of shrinkage-induced strain on the mechanical Q-factor of polymeric bridge-like resonators. Additionally, we report the status of our current developments using post-fabrication treatment of applying oxygen-plasma to further optimize the surface properties and aspect ratios of the structures.