Monolithically integrated polarization rotator and splitter with designed power ratio.

Area of Science:

• Photonics and Optical Engineering
• Computational Electromagnetics
• Device Design and Fabrication

Background:

• Inverse design methods are crucial for developing ultra-compact photonic devices.
• High computational power requirements due to optimization complexity limit current inverse design approaches.
• General Stokes' theorem offers a way to decompose complex systems into simpler building blocks.

Purpose of the Study:

• To develop a novel, computationally efficient inverse design methodology for optical devices.
• To leverage General Stokes' theorem for simplifying the optimization process.
• To validate the proposed methodology through the design and fabrication of a multi-functional photonic device.

Main Methods:

• Integration of General Stokes' theorem with inverse design principles.
• Application of separated regional optimization to reduce computational complexity.
• Design and experimental fabrication of a monolithically integrated polarization rotator and splitter.

Main Results:

• The new methodology reduced computational time by approximately five times compared to conventional inverse designs.
• The fabricated device successfully demonstrated polarization rotation and power splitting functionalities.
• Achieved an average insertion loss of less than 1 dB and crosstalk below -9.5 dB.

Conclusions:

• The proposed inverse design methodology significantly enhances computational efficiency for optical devices.
• The integration of General Stokes' theorem is feasible for designing complex, multi-functional monolithic photonic devices.
• This approach offers a promising direction for the development of advanced optical components.