Figure-9 mode-locked fiber laser using liquid crystal variable retarders.

Area of Science:

• Laser Physics
• Optoelectronics
• Nonlinear Optics

Background:

• Mode-locked fiber lasers are crucial for generating ultrashort optical pulses.
• Traditional mode-locking mechanisms often involve mechanical components or complex setups.
• Controlling mode-locking states efficiently is essential for various laser applications.

Purpose of the Study:

• To propose and experimentally validate a new scheme for a Figure-9 mode-locked fiber laser.
• To investigate the use of liquid crystal variable retarders (LCs) for tunable control of mode-locking states.
• To explore the parameter space and understand the distribution of mode-locking states in the proposed laser system.

Main Methods:

• Utilizing liquid crystal variable retarders (LCs) with tunable splitting ratios and non-reciprocal phase shifts.
• Employing full-wave scanning of LCs oriented at -1/4π to the horizontal plane.
• Conducting experimental validation under quasi-symmetric conditions to confirm mode-locking state control.

Main Results:

• Demonstrated effective exploration of the parameter space through LC scanning.
• Confirmed the capability to control the mode-locking state by varying LC retardance.
• Mapped the distribution of mode-locking states, showing a conservative yet similar distribution compared to conventional schemes.

Conclusions:

• The proposed scheme offers a fast-response, all-optical solution for mode-locked fiber lasers.
• The use of LCs provides tunable control over laser parameters and mode-locking states.
• This innovative approach is suitable for advancements in laser technology, intelligent mode locking, and ultrafast dynamics research.