Fractal-like mechanical resonators with soft-clamped fundamental mode

TL;DR

This paper demonstrates that fractal-like tensioned string resonators can significantly enhance mechanical quality factors through dissipation dilution, enabling advancements in precision sensing and quantum experiments.

Contribution

It introduces a novel fractal-inspired resonator design that markedly improves the fundamental mode quality factor over traditional strings.

Findings

Quality factor enhanced by up to two orders of magnitude.

Design applicable to force sensing and quantum optomechanics.

Potential for improved suspended test mass experiments.

Abstract

Self-similar structures occur naturally and have been employed to engineer exotic physical properties. Here we show that acoustic modes of a fractal-like system of tensioned strings can display increased mechanical quality factors due to the enhancement of dissipation dilution. We describe a realistic resonator design in which the quality factor of the fundamental mode is enhanced by as much as two orders of magnitude compared to a simple string with the same size and tension. Our findings can open new avenues in force sensing, cavity quantum optomechanics and experiments with suspended test masses.