High efficiency second harmonic generation in transverse orientation patterned gallium phosphide waveguides

Area of Science:

• Integrated photonics
• Nonlinear optics
• Materials science

Background:

• High conversion efficiencies in second-order nonlinear optical processes are crucial for integrated photonics.
• Achieving efficient second harmonic generation (SHG) in waveguides remains a significant challenge.

Purpose of the Study:

• To demonstrate the first transverse orientation-patterned gallium phosphide (TOP-GaP) waveguides for high-efficiency SHG.
• To explore the potential of TOP-GaP in advancing nonlinear optical applications.

Main Methods:

• Fabrication of TOP-GaP waveguides.
• Theoretical analysis of modal phase matching in TOP structures.
• Linear and nonlinear characterization of the waveguides.

Main Results:

• Demonstration of high-efficiency second harmonic generation in TOP-GaP waveguides.
• Successful implementation of first-order modal phase matching through vertical nonlinear susceptibility inversion.
• Detailed characterization of waveguide performance.

Conclusions:

• TOP-GaP waveguides offer a promising platform for efficient nonlinear optical processes.
• The presented approach enables optimized modal phase matching for enhanced SHG.
• This work paves the way for advanced integrated photonic devices for classical and quantum applications.