High-speed polarization control in integrated silicon photonics.

Area of Science:

• Photonics
• Integrated Circuits
• Optical Engineering

Background:

• Inverse design and adjoint methods are advancing ultra-compact photonic integrated circuits (PICs).
• High-speed polarization control is essential for efficient data transmission in optical communication systems.

Purpose of the Study:

• To design and implement an advanced, high-speed polarization control system using inverse design.
• To demonstrate an ultra-compact polarization beam rotator-splitter (PBRS) integrated with a phase shifter on a silicon photonics platform.

Main Methods:

• Utilized inverse design to create an ultra-compact PBRS (17 μm).
• Integrated the PBRS with a high-speed PN junction phase shifter and a plasma dispersion modulator within a Mach-Zehnder interferometer.
• Employed silicon photonics platform for device fabrication and testing.

Main Results:

• Achieved an ultra-compact PBRS with insertion loss < 1.0 dB (C-Band) and extinction ratio > 20 dB.
• Demonstrated rapid polarization state changes using the integrated plasma dispersion modulator.
• Successfully operated the polarization control optical circuit at 32 Gbit/s at 1550 nm.

Conclusions:

• The inverse-designed PBRS combined with a high-speed modulator offers a viable solution for advanced, high-speed polarization control in PICs.
• This technology holds significant potential for next-generation optical communication and computing applications.