Efficient type II second harmonic generation in an indium gallium phosphide on insulator wire waveguide aligned with...

Area of Science:

• Photonics
• Nonlinear Optics
• Semiconductor Nanophotonics

Background:

• Second harmonic generation (SHG) is crucial for frequency conversion.
• III-V-on-insulator (InP/SiN) platforms offer potential for integrated photonics.
• Type II SHG in waveguides requires careful phase-matching and field engineering.

Purpose of the Study:

• Investigate type II second harmonic generation (SHG) in III-V-on-insulator wire waveguides.
• Explore the role of propagation direction and field components in SHG.
• Compare type II SHG performance with type I SHG.

Main Methods:

• Theoretical modeling of nonlinear optical processes.
• Experimental fabrication and characterization of III-V-on-insulator wire waveguides.
• Measurement of SHG conversion efficiency under varying conditions.

Main Results:

• Propagation direction significantly impacts SHG efficiency.
• Longitudinal field components enhance SHG robustness and efficiency.
• Theoretical maximum conversion for type II SHG exceeds type I for similar dimensions.
• Experimental SHG conversion efficiency reached 12%/W.

Conclusions:

• Type II SHG in III-V-on-insulator waveguides is a viable route for efficient frequency conversion.
• Optimizing propagation direction and utilizing longitudinal fields are key for performance.
• Propagation loss currently limits experimental efficiency, indicating areas for future improvement.