Electroabsorption-modulated widely tunable DBR laser transmitter for WDM-PONs

Area of Science:

• Optoelectronics
• Semiconductor Lasers
• Photonics

Background:

• Passive optical networks (PONs) are crucial for broadband access.
• Wavelength Division Multiplexing (WDM) enhances fiber capacity.
• Developing cost-effective, high-performance transmitters is essential for WDM-PON.

Purpose of the Study:

• To present a novel InP-based distributed Bragg reflector (DBR) laser transmitter.
• To achieve a wide wavelength tuning range and high output power for WDM-PON.
• To demonstrate a simple fabrication process for low-cost mass production.

Main Methods:

• Utilized Indium Phosphide (InP) material for the DBR laser.
• Employed butt-jointing of InGaAsP (1.45 µm emission) for the grating section.
• Integrated a semiconductor optical amplifier (SOA) and an electroabsorption modulator (EAM) using selective-area growth (SAG).

Main Results:

• Achieved a wavelength tuning range over 13 nm via DBR current, expandable to 16 nm with temperature control.
• Obtained a maximum chip output power exceeding 30 mW with the integrated SOA.
• Demonstrated a 3 dB small signal modulation bandwidth over 13 GHz for the integrated EAM.

Conclusions:

• The developed DBR laser transmitter meets key performance metrics for WDM-PON.
• The simple tuning scheme and fabrication process are suitable for low-cost, high-volume WDM-PON deployment.
• This technology offers a promising solution for next-generation optical access networks.