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Updated: Jul 4, 2026
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Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
Coupled whispering gallery mode resonators in the Terahertz frequency range
S Preu1, H G L Schwefel, S Malzer
1Max Planck Research Group, Institute for Optics, Information and Photonics, University of Erlangen-Nürnberg, D-91058 Erlangen, Germany. spreu@optik.uni-erlangen.de
Optics Express
|June 12, 2008
Summary
We demonstrate coupling two macroscopic whispering gallery mode resonators in the Terahertz range. This coupling results in observable mode splitting, matching theoretical predictions for these high-frequency devices.
Area of Science:
- Optics and Photonics
- Terahertz (THz) Science and Technology
- Resonator Physics
Background:
- Whispering gallery mode resonators offer high-Q factors for various applications.
- Macroscopic resonators in the Terahertz (THz) range allow for precise fabrication and mode control.
- Coupling of resonators is crucial for advanced photonic integrated circuits and sensing.
Purpose of the Study:
- To investigate the coupling of two macroscopic whispering gallery mode resonators in the THz frequency range.
- To analyze the effects of resonator size, shape, and loading on resonance properties.
- To experimentally verify theoretical predictions of mode splitting in coupled resonator systems.
Main Methods:
- Fabrication of macroscopic disk resonators using polyethylene (PE) and quartz.
- Characterization of resonator properties, including quality (Q)-factors and resonance spectra.
- Experimental coupling of two identical resonators and measurement of resulting mode splitting.
Main Results:
- Demonstrated resonators with medium loaded Q-factors ranging from 40 to 800.
- Observed coinciding resonance frequency spectra over more than ten times the free spectral range.
- Measured significant Q-factor degradation and a 0.2% red-shift in resonance frequencies due to loading effects.
- Reported clear mode splitting upon coupling two identical resonators, consistent with numerical calculations.
Conclusions:
- Macroscopic THz whispering gallery mode resonators can be accurately controlled for specific mode coupling.
- Coupling of identical resonators leads to observable mode splitting, validating theoretical models.
- Loading effects significantly impact resonator Q-factors and resonance frequencies, requiring careful consideration in device design.
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