InP high power monolithically integrated widely tunable laser and SOA array for hybrid integration

Area of Science:

• Photonics
• Integrated Optics
• Semiconductor Lasers

Background:

• Photonic integrated circuits (PICs) are crucial for miniaturizing optical systems.
• High-power, narrow-linewidth laser sources are essential for nonlinear integrated photonics.
• On-chip coherent beam combination offers a pathway to increased optical power.

Purpose of the Study:

• To demonstrate a monolithic indium phosphide (InP)-based PIC for high-power laser generation.
• To achieve stable and efficient on-chip coherent beam combination of multiple amplifiers.
• To explore hybrid integration with silicon nitride microring resonators for linewidth narrowing.

Main Methods:

• Fabrication of a monolithic InP PIC with a tunable laser and amplifier array.
• On-chip interferometric combination of semiconductor optical amplifiers in a single-mode waveguide.
• Hybrid integration with a high-quality factor silicon nitride microring resonator for external cavity feedback.

Main Results:

• Demonstrated stable on-chip coherent beam combination with up to 240 mW average power.
• Achieved 30-50 kHz Schawlow-Townes linewidths and >180 mW average power across the extended C-band.
• Hybrid integration yielded a narrowed linewidth of ~3 kHz with 37.9 mW average power.

Conclusions:

• The developed InP-based PIC is a promising platform for high-power, narrow-linewidth laser sources.
• On-chip coherent beam combination is an effective strategy for power scaling.
• Hybrid integration with microring resonators offers a route to ultra-narrow linewidths for integrated photonics.