Compensation for fabrication-induced center wavelength shift in a coupled waveguide type multi/demultiplexer

Area of Science:

• Photonics and Optical Engineering
• Materials Science

Background:

• Fabrication errors in optical devices like multi/demultiplexers can cause critical wavelength shifts.
• Existing methods may struggle to precisely control these shifts, impacting device performance.

Purpose of the Study:

• To propose a new coupled waveguide multi/demultiplexer design.
• To develop a fabrication method that actively compensates for wavelength shifts (Δλ₀) arising from fabrication inaccuracies.

Main Methods:

• A waveguide structure embedded in a cladding layer with a tunable refractive index (n<0xE1><0xB5><0x9C>) is designed.
• The optimal n<0xE1><0xB5><0x9C> is calculated based on measured deviations in core width, height, and waveguide separation.
• A cladding material with the calculated optimal n<0xE1><0xB5><0x9C> is applied to the entire waveguide structure.

Main Results:

• The proposed method effectively compensates for wavelength shifts (Δλ₀) caused by fabrication errors.
• Optimization of the cladding refractive index (n<0xE1><0xB5><0x9C>) allows for precise control over the multi/demultiplexer's operating wavelength.

Conclusions:

• The developed fabrication technique enables the production of accurate coupled waveguide multi/demultiplexers.
• This approach offers a viable solution for mitigating wavelength shifts in photonic integrated circuits.