Radio frequency interrogated actively mode-locked fiber ring laser for sensing application

Area of Science:

• Photonics and Laser Technology
• Optical Sensing
• Fiber Optic Systems

Background:

• Fiber ring lasers are versatile optical sources.
• Active mode-locking offers precise temporal control.
• Optical frequency combs have diverse applications.

Purpose of the Study:

• To propose and demonstrate an actively mode-locked fiber ring laser for sensing applications.
• To investigate the relationship between cavity length and frequency comb characteristics.
• To showcase the device's capability for temperature measurement.

Main Methods:

• An electro-optic amplitude modulator was used to achieve active mode-locking.
• The laser's radio frequency (RF) drive matched the longitudinal mode beat frequency.
• Cavity length variations were induced and their effect on the frequency comb analyzed.

Main Results:

• The frequency separation of the generated optical frequency comb showed a linear dependence on cavity length changes.
• The sensing mechanism based on this linear relationship was validated.
• Accurate temperature measurements were successfully demonstrated using the developed laser system.

Conclusions:

• The actively mode-locked fiber ring laser provides a robust platform for optical sensing.
• The linear relationship between cavity length and frequency comb spacing is a key sensing parameter.
• This technology holds promise for high-precision environmental monitoring, particularly temperature sensing.