Dual-ring resonators for uniform optical frequency combs
Solution Overview
Problem
Existing optical frequency comb generators face challenges in producing a broad and uniform optical power spectrum, which is essential for improving the compactness, stability, and spectral density of WDM or DWDM systems while reducing power requirements.
Innovation Solution
The use of dual-ring resonators with varying optical waveguide widths in photonic integrated circuits, where one waveguide core has a different width in different sections to achieve flattened dispersion spectra, allowing for resonant optical coupling at multiple wavelengths and reduced mode dispersion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If integrated micro-resonators are used as optical frequency comb generators, then compactness and stability are improved, but the optical power spectrum uniformity deteriorates
Solution Approach 1:
The waveguide width is varied locally along the resonator path to provide dispersion compensation. Specifically, the waveguide width changes from a first value to a second value in different sections of the resonator, creating localized modifications to the dispersion characteristics that collectively flatten the overall optical power spectrum across the frequency comb
Solution Approach 2:
The waveguide geometric parameters (width or height) are changed to modify the dispersion properties of the resonator. By adjusting the waveguide width or height along different sections, the effective dispersion is compensated to achieve uniform spectral distribution while maintaining the compact integrated structure
2Adaptability or versatility
If broad spectral width is achieved in frequency combs, then spectral density is improved, but mode dispersion increases
Solution Approach 1:
The waveguide dimensions are modified along the resonator to provide dispersion compensation that enables broad spectral width while maintaining low mode dispersion. The parameter changes in waveguide width or height create a flattened dispersion spectrum that supports wide bandwidth operation with uniform mode spacing
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables the generation of expanded and uniform frequency combs with reduced integrated dispersion, enhancing the spectral width and stability of the optical frequency comb, thereby improving the performance of WDM or DWDM systems.
Implementation Method 1
adjacent segments of the optical waveguide cores being evanescently optically coupled
Implementation Method 2
the optical waveguide cores resonantly optically couple at two separated wavelength regions
Data Source
AI summary
A planar optical resonator capable of parametrically generating frequency combs includes two optical waveguide cores forming inner and outer loops, the resonator having two sections, in which laterally adjacent segments of the cores are resonantly optically coupled to each other at two separate wavelength regions causing separate peaks in the second order dispersion. The resonator sections may be configured to suppress integrated dispersion of the resonator in a broad spectral range favorably for generating a spectrally uniform frequency comb.