Related Experiment Video
Updated: Jun 6, 2025
12:18
Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
16.9K
Asymmetric χ(2)-translated optical frequency combs assisted by avoided mode crossing in concentric ring resonators
Optics Express
|November 22, 2024
Summary
We demonstrate asymmetric optical frequency combs generated by the interplay of second- and third-order nonlinearities in microresonators. This novel approach enables tailored comb generation for applications in frequency metrology.
Area of Science:
- Nonlinear optics
- Integrated photonics
- Microresonator devices
Background:
- Microcomb generation leverages nonlinear optical responses in microresonators.
- Interplay between second- (χ(2)) and third-order (χ(3)) nonlinearities offers potential for broadband comb sources.
- Wavelength dependence of coupling coefficients is often overlooked.
Purpose of the Study:
- To investigate the spectral response of coupled χ(2) and χ(3) nonlinearities in microresonators.
- To propose a new approach for controlling optical frequency comb generation.
- To explore the impact of avoided mode crossing (AMX) on comb asymmetry.
Main Methods:
- Theoretical modeling of coupled nonlinearities in microresonators.
- Numerical simulations of optical frequency comb generation.
- Utilizing concentric double-ring microresonators to achieve AMX.
- Analyzing spectral asymmetry in generated combs.
Main Results:
- Demonstrated asymmetric χ(2)-translated optical frequency combs at second-harmonic wavelengths.
- Achieved simultaneous generation of skewed two-color optical frequency combs.
- Numerical realization in a gallium phosphide-on-insulator platform.
- Model shows reasonable agreement with numerical results.
Conclusions:
- The interplay of χ(2) and χ(3) nonlinearities, enabled by AMX, provides a method for shaping optical frequency combs.
- Asymmetric comb generation is driven by the disruption of spectral symmetry.
- Findings facilitate applications in self-referencing and frequency metrology with controlled comb shapes.
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