MOCVD-grown InAs/InP quantum dot lasers with low threshold current.

Area of Science:

• Materials Science
• Optoelectronics
• Semiconductor Physics

Background:

• Quantum dot lasers are crucial for optical communication.
• Achieving high performance in InAs/InP quantum dots remains challenging.

Purpose of the Study:

• To develop low-threshold, high-yield InAs/InP quantum dot lasers.
• To optimize MOCVD growth for improved quantum dot quality and laser performance.

Main Methods:

• Metal-organic chemical vapor deposition (MOCVD) for InAs/InP quantum dot growth.
• Optimization of epitaxial conditions, including GaAs interfacial layers.
• Fabrication of deep-etched ridge waveguide lasers with specific dimensions.
• Characterization under pulsed injection and temperature-dependent measurements.

Main Results:

• Achieved in-plane symmetric quantum dots with enhanced optical quality.
• Demonstrated low threshold currents of 17 mA (300 μm) and 28 mA (1000 μm).
• Lasing sustained up to 120°C with a characteristic temperature (T0) of 74.9 K below 90°C.

Conclusions:

• Optimized MOCVD growth yields high-quality InAs/InP quantum dots for lasers.
• Fabricated lasers demonstrate excellent performance metrics, including low thresholds and high-temperature stability.
• These devices are promising for C- and L-band optical communication applications.