Chip-based soliton microcomb module using a hybrid semiconductor laser.

Area of Science:

• Photonics
• Nonlinear Optics
• Integrated Photonics

Background:

• Soliton microcombs on photonic chips are advancing rapidly for system applications.
• Compact laser sources are key, but generating single solitons with detectable repetition rates remains a challenge.

Purpose of the Study:

• To demonstrate a current-initiated, silicon nitride chip-based soliton microcomb.
• To achieve single soliton generation with electronically detectable repetition rates from a compact laser module.
• To develop a reliable packaging technique for fiber-chip interfacing.

Main Methods:

• Utilized a silicon nitride (Si3N4) chip-based platform.
• Employed a compact, semiconductor-based laser as the pump source.
• Demonstrated current-initiated soliton formation and tuning via laser current adjustment.
• Developed a generic, simple, and reliable packaging technique for fiber-chip interface.

Main Results:

• Successfully generated a 99-GHz soliton microcomb driven directly by a compact semiconductor laser.
• Achieved single soliton generation without complex tuning techniques, controllable by laser current.
• Demonstrated a robust fiber-chip interface enabling high-power operation (> 100 mW).

Conclusions:

• The developed current-initiated soliton microcomb offers a simplified approach for generating single solitons.
• The packaging technique facilitates integration with existing fiber systems, enhancing usability.
• These advancements are crucial for chip-based nonlinear photonic applications requiring high power and fiber compatibility.