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Updated: Nov 26, 2025
12:18
Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
17.3K
Dominant Loss Mechanisms of Whispering Gallery Mode RF-MEMS Resonators with Wide Frequency Coverage
Zeji Chen1,2,3, Qianqian Jia1,2,3, Wenli Liu1,2,3
1Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.
Sensors (Basel, Switzerland)
|December 11, 2020
Summary
This study reveals dominant energy loss mechanisms in whispering gallery mode (WGM) resonators. Squeezed film damping is key in air, while Akhiezer damping and anchor loss dominate in vacuum, enhancing resonator performance.
Area of Science:
- Physics
- Materials Science
- Acoustics
Background:
- Whispering gallery mode (WGM) resonators are crucial for sensitive measurements.
- Understanding energy dissipation is vital for optimizing WGM resonator performance.
Purpose of the Study:
- To investigate dominant energy dissipation mechanisms in multi-frequency WGM resonators.
- To provide insights into the loss mechanisms affecting device performance.
Main Methods:
- Developed theoretical models for various loss sources.
- Experimentally validated theoretical predictions.
- Analyzed loss mechanisms under atmospheric and vacuum conditions.
Main Results:
- Squeezed film damping (SFD) identified as a major loss in air for all WGMs.
- In vacuum, frequency-dependent Akhiezer damping (AKE) significantly impacts different modes.
- For low-order WGMs, anchor loss dominates; for high-order modes, AKE is the primary factor limiting Q values.
Conclusions:
- Achieved substantial Q enhancements (over four times).
- Demonstrated an excellent figure of merit (f × Q product) up to 6.36 × 10^13 at 7 K.
- Established a framework for understanding and mitigating losses in WGM resonators.
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