All-fiber hectowatt radially polarized laser system

Area of Science:

• Optics and Photonics
• Laser Technology
• Fiber Optics

Background:

• Radially polarized beams offer unique advantages in laser applications.
• Generating high-power radially polarized beams in all-fiber systems remains challenging.

Purpose of the Study:

• To demonstrate a high-power all-fiber laser system producing a radially polarized beam.
• To achieve high output power without compromising beam quality.

Main Methods:

• Utilized an integrated nanograting mode converter (S-wave plate) for radial polarization generation.
• Employed a single-stage few-mode fiber amplifier to boost laser power.
• Characterized mode purity and mode extinction ratio (MER) of the amplified beam.

Main Results:

• Achieved an average output power of 113.2 W from a 1-W seed laser.
• Maintained high mode purity (95.7%) and MER (97%) after amplification.
• Reported a slope efficiency of approximately 72% and a beam quality factor (M² ) of 2.3.

Conclusions:

• This work represents the highest output power achieved for an all-fiber radially polarized laser system.
• The demonstrated system maintains excellent beam quality metrics, paving the way for advanced applications.