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Updated: Jun 4, 2026
10:26
Fabrication and Characterization of Superconducting Resonators
Published on: May 21, 2016
Planar coupling to high-Q lithium niobate disk resonators
G Nunzi Conti1, S Berneschi, F Cosi
1NelloCarrara Institute of Applied Physics, IFAC-CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino, Firenze, Italy. g.nunziconti@ifac.cnr.it
Optics Express
|March 4, 2011
Summary
Researchers achieved optical coupling to high-Q lithium niobate (LiNbO3) disks using integrated waveguides. This method is promising for practical applications of whispering gallery mode resonators.
Area of Science:
- Photonics and Material Science
- Optoelectronics
Background:
- Whispering gallery mode (WGM) resonators offer high quality factors (Q) for various photonic applications.
- Lithium niobate (LiNbO3) is a key material for nonlinear optics and integrated photonics.
- Efficiently coupling light into high-Q LiNbO3 resonators is crucial for device performance.
Purpose of the Study:
- To demonstrate efficient optical coupling between integrated lithium niobate waveguides and high-Q lithium niobate disks.
- To characterize the Q factor of the fabricated lithium niobate disk resonators.
Main Methods:
- Fabrication of integrated lithium niobate waveguides via proton exchange in X-cut LiNbO3.
- Manufacturing of LiNbO3 disks (4.7 mm diameter, 1 mm thickness) from Z-cut wafers with spheroidal profiles.
- Measurement of resonator Q factor using resonance linewidth and cavity ringdown techniques.
Main Results:
- Successful optical coupling from integrated waveguides to LiNbO3 disks.
- Achieved Q factors exceeding 10^8 for the LiNbO3 disk resonators.
- Demonstrated planar coupling as a viable technique for WGM resonator integration.
Conclusions:
- Integrated lithium niobate waveguides enable efficient coupling to high-Q LiNbO3 disk resonators.
- The demonstrated planar coupling method is highly promising for practical photonic devices.
- High-Q LiNbO3 resonators are achievable with precise fabrication and coupling techniques.
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