High-tolerance reconfigurable MZI racetrack resonator on a 3-µm-thick SOI photonics platform.

Area of Science:

• Photonics
• Integrated Circuits
• Materials Science

Background:

• The 3-µm-thick silicon-on-insulator (SOI) platform is crucial for integrated photonics.
• Resonator integration presents challenges for device performance and fabrication tolerance.

Purpose of the Study:

• To propose and demonstrate an integrated resonator with high fabrication tolerance and reconfigurability.
• To expand the device library for the 3-µm-thick SOI photonics platform.

Main Methods:

• Utilized a deep-etch silicon waveguide for resonator fabrication.
• Employed tunable multimode interferometers (MMIs) for coupler-based reconfigurability.
• Characterized device performance in critical-coupling (filter) and extreme over-coupling (delay line) states.

Main Results:

• Achieved filter operation with an extinction ratio (ER) of 23.5 dB and a quality (Q) factor of 3.1×10⁵ in the 1530-1570 nm range.
• Demonstrated a large-bandwidth delay line with a continuous delay time change of 22 ps, nearly independent of wavelength.
• The resonator exhibits high fabrication tolerance and reconfigurability.

Conclusions:

• The proposed integrated resonator enhances the capabilities of the 3-µm-thick SOI platform.
• The device offers versatile functionalities as both a filter and a delay line.
• This work enriches the application potential of silicon photonics.