Maximizing power output from continuous-wave single-frequency fiber amplifiers

Area of Science:

• Photonics
• Fiber Optics
• Laser Technology

Background:

• Highly saturated fiber amplifiers are crucial for high-power lasers.
• Stimulated Brillouin scattering (SBS) and transverse modal instability (TMI) limit output power.
• Optimizing fiber design is key to overcoming these limitations.

Purpose of the Study:

• To develop a method for maximizing power output in cladding-pumped continuous-wave single-frequency fiber amplifiers.
• To identify key parameters influencing power maximization, including SBS and TMI thresholds.
• To numerically analyze different fiber designs for improved performance.

Main Methods:

• Developed a design figure of merit incorporating fundamental mode overlap, peak Brillouin gain, and peak mode coupling gain.
• Numerically analyzed standard, segmented acoustically tailored, and micro-segmented acoustically tailored photonic-crystal fibers.
• Evaluated the impact of fiber design on SBS and TMI thresholds.

Main Results:

• The design figure of merit effectively predicts power output limitations.
• Segmented and micro-segmented acoustically tailored photonic-crystal fibers show significant potential.
• These advanced fiber designs are predicted to enable 50% higher output power than standard photonic crystal fibers.

Conclusions:

• Advanced fiber designs, particularly acoustically tailored photonic-crystal fibers, offer a pathway to significantly increase power output.
• The proposed design methodology provides a framework for optimizing fiber amplifiers for high-power applications.
• This research contributes to the development of more efficient and powerful fiber laser systems.