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Fractal-like Mechanical Resonators with a Soft-Clamped Fundamental Mode
S A Fedorov1, A Beccari1, N J Engelsen1
1Institute of Physics (IPHYS), École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
Physical Review Letters
|February 1, 2020
Summary
Fractal-like acoustic resonators made of tensioned strings significantly enhance mechanical quality factors by diluting dissipation. This breakthrough boosts resonator performance by up to 100 times, enabling advanced applications.
Area of Science:
- Acoustics
- Mechanical Engineering
- Materials Science
Background:
- Self-similar structures are found in nature and used to create unique physical properties.
- Acoustic resonators are crucial for various sensing and quantum technologies.
Purpose of the Study:
- To investigate the acoustic properties of fractal-like systems of tensioned strings.
- To demonstrate enhanced mechanical quality factors in such systems.
- To explore potential applications in advanced scientific experiments.
Main Methods:
- Modeling and simulation of acoustic modes in fractal-like string resonators.
- Analysis of dissipation dilution mechanisms.
- Comparison with simple string resonators.
Main Results:
- Acoustic modes in fractal-like string systems exhibit significantly enhanced mechanical quality factors.
- Quality factor enhancement of up to 2 orders of magnitude was achieved for the fundamental mode.
- Dissipation dilution was identified as the key mechanism for this enhancement.
Conclusions:
- Fractal-like string resonators offer a novel approach to engineering high-quality factor acoustic devices.
- These findings have implications for developing sensitive force sensors, cavity quantum optomechanics, and experiments with suspended masses.
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