Characterization of integrated photonic devices with minimum phase technique

Area of Science:

• Photonics and Optical Engineering
• Materials Science

Background:

• Spurious reflections, especially facet reflections in high refractive index platforms (Indium Phosphide (InP), Silicon-on-Insulator (SOI)), hinder accurate characterization of integrated optical devices.
• The absence of anti-reflective (AR) coatings exacerbates reflection issues in these platforms.

Purpose of the Study:

• To present a novel method for recovering original device characteristics from measured power transmission data affected by spurious reflections.
• To enable accurate experimental characterization of integrated optical devices without relying on AR coatings.

Main Methods:

• Utilizing minimum phase techniques to reconstruct time-domain information from measured power transmission.
• Filtering the reconstructed time-domain data to eliminate reflection artifacts.
• Providing a criterion to assess device suitability for the minimum phase technique.

Main Results:

• Successfully recovered original device characteristics by removing reflection artifacts.
• Validated the technique using simulated and experimental results for multi-mode interference couplers (MMICs) in SOI.
• Demonstrated the effectiveness of the method in the absence of anti-reflective coatings.

Conclusions:

• The proposed minimum phase technique effectively removes spurious reflection artifacts from optical device measurements.
• This method provides a viable solution for accurate characterization of integrated optical devices on high refractive index platforms without AR coatings.
• The technique is validated for MMICs in SOI, showing its practical applicability.