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Updated: Jul 7, 2026
10:26
Fabrication and Characterization of Superconducting Resonators
Published on: May 21, 2016
Langasite, langanite, and langatate bulk-wave Y-cut resonators
R C Smythe1, R C Helmbold, G E Hague
1Piezo Technol. Inc., Orlando, FL.
Summary
Langasite family materials, including LGS, LGN, and LGT, show promise for bulk wave devices. Their temperature-frequency dependence is parabolic, with LGN and LGT exceeding AT-cut quartz performance.
Area of Science:
- Materials Science
- Solid State Physics
- Acoustic Devices
Background:
- Langasite family materials (LGS, LGN, LGT) are crucial for advanced bulk and surface wave devices.
- Understanding their electromechanical properties is key to optimizing resonator performance.
Purpose of the Study:
- To evaluate the performance of Y-cut langasite, langanite, and langatate bulk wave resonators.
- To compare experimental results with theoretical calculations for frequency and motional inductance.
- To assess the temperature-frequency characteristics and Q-frequency products of these materials.
Main Methods:
- Fabrication and testing of piano-convex Y-cut bulk wave resonators using LGS, LGN, and LGT.
- Measurement of resonant frequencies and motional inductances across overtones 1-9.
- Analysis of frequency variation with temperature and determination of Q-frequency products.
Main Results:
- Experimental frequencies and motional inductances showed good agreement with calculations, except for LGT's motional inductance.
- Frequency variation with temperature followed a parabolic trend for all tested materials.
- LGN and LGT demonstrated Q-frequency products significantly exceeding the classical limit for AT-cut quartz.
- A maximum 4f value of 29.2x10^6 (MHz) was measured for an unplated LGT resonator.
Conclusions:
- Langasite family materials are highly suitable for high-performance bulk wave resonators.
- LGN and LGT offer superior electromechanical coupling and temperature stability compared to traditional quartz.
- Further optimization may lead to even higher performance metrics for these advanced materials.
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