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Updated: Aug 5, 2026
12:18
Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
Threshold reduction of phonon lasing in coupled microresonators with a feedback waveguide
Optics Letters
|July 31, 2026
Summary
Researchers developed a novel feedback waveguide scheme to significantly reduce the threshold power required for phonon lasing in coupled microresonators. This method enhances mechanical gain, offering a simpler and more efficient experimental approach.
Area of Science:
- Optics and Photonics
- Quantum Acoustics
- Materials Science
Background:
- Phonon lasing in coupled microresonators is crucial for quantum acoustics applications.
- Existing experimental schemes face limitations in threshold power requirements.
- Improving mechanical gain is key to efficient phonon lasing.
Purpose of the Study:
- To propose a novel scheme for reducing the threshold power of phonon lasing.
- To investigate a new physical mechanism for enhancing mechanical gain.
- To provide a feasible experimental method for phonon lasing.
Main Methods:
- Introduction of a feedback waveguide into coupled microresonators.
- Analysis of nonreciprocal coupling and constructive interference for mechanical gain.
- Calculation of the second-order coherence degree to confirm phonon lasing.
Main Results:
- The proposed scheme reduces the threshold power by half compared to previous experiments.
- A new physical mechanism involving nonreciprocal coupling and constructive interference was identified.
- The second-order coherence degree confirms effective phonon lasing at reduced power.
Conclusions:
- The feedback waveguide scheme offers a significant reduction in threshold power for phonon lasing.
- The identified mechanism provides a novel pathway for enhancing mechanical gain.
- This simple and feasible scheme is a valuable addition to experimental methods in phonon lasing.
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