Interband optical pulse injection locking of quantum dot mode-locked semiconductor laser

Area of Science:

• Quantum optics
• Semiconductor laser physics

Background:

• Quantum dot (QD) lasers offer unique properties for optical signal processing.
• Mode-locked semiconductor lasers are crucial for generating optical pulse trains.
• Optical clock recovery is essential for high-speed optical communication systems.

Purpose of the Study:

• To experimentally demonstrate optical clock recovery in quantum dot mode-locked semiconductor lasers.
• To investigate the effects of interband optical pulse injection locking on laser dynamics.
• To analyze the locking bandwidth and behavior under different injection configurations.

Main Methods:

• Utilizing a master-slave laser configuration for optical injection locking.
• Employing quantum dot mode-locked semiconductor lasers operating on ground state and first excited state transitions.
• Injecting optical pulses generated from opposite transition bands (interband injection).

Main Results:

• Successful optical clock recovery was achieved via interband optical pulse injection locking.
• Asymmetric locking bandwidth observed when injecting from the first excited state to the ground state.
• No locking occurred in the reverse injection case (ground to first excited state) at nominal rates, but locking was achieved at higher injection rates with a 6.7 MHz bandwidth.

Conclusions:

• Interband optical pulse injection locking is a viable method for optical clock recovery in quantum dot lasers.
• The transition band used for injection significantly influences the locking dynamics and bandwidth.
• Further research into optimizing injection parameters can enhance clock recovery performance.