Widely tunable narrow-linewidth lasers with booster amplification on silicon photonics

Area of Science:

• Photonics and Materials Science
• Integrated Optics
• Semiconductor Device Engineering

Background:

• Silicon photonics (SiPh) platforms face challenges in developing widely tunable lasers with high power, narrow linewidth, and low relative intensity noise (RIN).
• Existing solutions often struggle to meet the stringent requirements for advanced applications like wavelength-division multiplexing (WDM) and photonic sensing.
• On-chip laser integration is crucial for compact and scalable photonic systems.

Purpose of the Study:

• To demonstrate a novel method for fabricating widely tunable lasers on SiPh platforms.
• To achieve simultaneous control over laser cavity gain and output amplification using a double-ridge semiconductor optical amplifier (SOA) structure.
• To enable high-performance, compact laser-based photonic systems-on-chip.

Main Methods:

• Micro-transfer printing of double-ridge InP/InGaAs semiconductor optical amplifiers (SOAs) onto a SiPh platform.
• Integration of SOAs to enable simultaneous control of laser cavity gain and optical amplification.
• Characterization of the tunable laser performance, including tuning range, output power, linewidth, and RIN.

Main Results:

• Achieved a widely tunable laser with a tuning range exceeding 51 nm.
• Delivered a waveguide-coupled output power of 10 mW per wavelength.
• Demonstrated a narrow linewidth of 1.6 kHz and a low RIN of approximately -140 dB/Hz.

Conclusions:

• The developed double-ridge SOA structure effectively enables on-chip widely tunable lasers with superior performance.
• The micro-transfer printing approach provides a viable pathway for high-performance laser integration on SiPh platforms.
• The resulting lasers are suitable for demanding applications in WDM systems and photonic sensing, paving the way for advanced photonic integrated circuits.