Transversely coupled Fabry-Perot resonators with Bragg grating reflectors.

Area of Science:

• Photonics and Optical Engineering
• Integrated Optics
• Semiconductor Devices

Background:

• Fabry-Perot resonators are crucial optical components.
• Silicon-on-insulator (SOI) platform offers advantages for integrated photonics.
• Bragg gratings are effective for creating high-reflectivity mirrors.

Purpose of the Study:

• To design and demonstrate Fabry-Perot resonators with transverse coupling on SOI.
• To investigate the impact of cavity length and coupling coefficient on spectral properties.
• To achieve high extinction ratios and Q-factors in SOI-based resonators.

Main Methods:

• Utilizing Bragg gratings as reflectors for Fabry-Perot cavities.
• Employing transverse coupling in the resonator design.
• Fabricating devices on the silicon-on-insulator (SOI) platform.
• Characterizing spectral properties, including extinction ratio (ER) and Q-factor.

Main Results:

• Demonstrated Fabry-Perot resonators with ER up to 37.28 dB and Q-factor of 3356 (110 μm cavity).
• Achieved ER of 8.69 dB and Q-factor of 23642 for a 943 μm cavity.
• Obtained the highest reported extinction ratio for SOI resonators.
• Showcased enhanced tunability compared to all-pass ring resonators.

Conclusions:

• The developed Bragg grating-based Fabry-Perot resonators on SOI offer superior spectral control.
• These resonators provide a versatile platform for advanced photonic integrated circuits.
• The design achieves record extinction ratios, enabling high-performance optical filtering and sensing applications.