High power all-fiber amplifier with different seed power injection

Area of Science:

• Optics and Photonics
• Laser Technology
• Fiber Optics

Background:

• High-power fiber amplifiers are crucial for various applications, including material processing and telecommunications.
• Stimulated Raman scattering (SRS) is a limiting nonlinear effect in high-power fiber amplifiers.
• Controlling SRS is essential for achieving high output power and maintaining beam quality.

Purpose of the Study:

• To investigate the relationship between injected seed power and the stimulated Raman scattering (SRS) threshold in an all-fiber amplifier.
• To achieve high-power output with good beam quality from an all-fiber amplifier.
• To optimize amplification parameters for efficient power delivery.

Main Methods:

• An all-fiber laser was used to provide seed power for an all-fiber amplifier.
• Experiments were conducted by injecting varying seed power levels into the amplifier.
• Output power, beam quality (M²), and slope efficiency were measured.

Main Results:

• The stimulated Raman scattering (SRS) threshold was found to be inversely proportional to the injected seed power.
• More than 3 kW of signal light was successfully amplified.
• The amplified signal light exhibited good beam quality with an M² value of 1.28.
• A high slope efficiency of approximately 84.4% was achieved.

Conclusions:

• Optimizing seed power is critical for suppressing stimulated Raman scattering (SRS) and achieving high-power output in all-fiber amplifiers.
• The developed all-fiber amplifier demonstrates a viable approach for generating high-power laser light with excellent beam quality.
• The findings provide valuable insights for the design and operation of future high-power fiber laser systems.