High speed data transmission using directly modulated microdisk lasers based on InGaAs/GaAs quantum well-dots

Area of Science:

• Optoelectronics
• Semiconductor Lasers
• Data Transmission

Background:

• Microdisk lasers offer potential for high-speed optical communication due to their compact size and efficient light confinement.
• Reliability and direct modulation capabilities are critical for practical deployment in data networks.

Purpose of the Study:

• To investigate the direct large-signal modulation performance of InGaAs/GaAs quantum well-dot microdisk lasers.
• To assess the reliability and long-term stability of these microdisk lasers under various temperature conditions.

Main Methods:

• Fabrication of microdisk lasers using InGaAs/GaAs quantum well-dot material.
• Characterization of modulation performance using eye diagram analysis up to 12.5 Gbit/s.
• Long-term aging tests conducted at room temperature (approx. 20-25°C) and elevated temperatures (40°C and 60°C) for over 1200 hours.

Main Results:

• A 23 μm diameter microdisk laser achieved an open eye diagram up to 12.5 Gbit/s.
• Error-free 10 Gbit/s data transmission was demonstrated at 30°C without active temperature stabilization.
• Aging tests showed a low average output power degradation rate of approximately 25-29 nW/hr at 40°C and 60°C, respectively.

Conclusions:

• InGaAs/GaAs quantum well-dot microdisk lasers exhibit promising direct modulation capabilities for high-speed data transmission.
• The demonstrated reliability and stable operation at elevated temperatures suggest suitability for demanding optical communication applications.