Intensity noise coupling in soliton fiber oscillators

Area of Science:

• Optics and Photonics
• Laser Physics
• Fiber Lasers

Background:

• Soliton fiber oscillators are crucial for generating ultrashort optical pulses.
• Understanding and mitigating intensity noise is essential for laser applications.
• Pump-to-output noise coupling impacts laser stability and performance.

Purpose of the Study:

• To experimentally and numerically investigate spectrally resolved pump-to-output intensity noise coupling in soliton fiber oscillators.
• To identify the primary mechanisms of noise coupling in these systems.
• To demonstrate methods for improving the intensity noise performance of soliton fiber lasers.

Main Methods:

• Experimental measurements of noise coupling in erbium- and holmium-doped fiber oscillators.
• Numerical modeling to confirm experimental observations and explore underlying physics.
• Analysis of noise coupling to Kelly sidebands and the soliton pulse spectrum.

Main Results:

• Observed strong pump noise coupling to Kelly sidebands.
• Demonstrated damped coupling of pump noise to the fundamental soliton pulse.
• Confirmed this behavior as a general feature in soliton-dominant laser oscillators.
• Showcased significant improvement in intensity noise by spectrally blocking Kelly sidebands.

Conclusions:

• Pump noise predominantly couples to Kelly sidebands, not the soliton pulse, in these lasers.
• Spectral filtering of Kelly sidebands is an effective strategy to enhance laser intensity noise performance.
• The findings offer a pathway for developing more stable and reliable soliton fiber laser systems.