1.01 kW superfluorescent source in all-fiberized MOPA configuration.

Area of Science:

• Laser Physics and Photonics
• Fiber Optic Technology
• High-Power Laser Systems

Background:

• Superfluorescent sources are crucial for various applications requiring high-power, broad-linewidth light.
• Existing fiber-based superfluorescent sources often face limitations in output power and beam quality.
• Master Oscillator Power Amplifier (MOPA) architectures are effective for power scaling in fiber lasers.

Purpose of the Study:

• To demonstrate a kilowatt-class all-fiberized superfluorescent source.
• To investigate the spectral evolution effects during broadband amplification in high-power superfluorescent systems.
• To achieve high beam quality alongside high output power.

Main Methods:

• Utilized a dual-cladding ytterbium-doped fiber for the superfluorescent source.
• Employed a homemade amplified spontaneous emission (ASE) source as the seed.
• Implemented a two-stage high-power fiber amplifier to boost seed power to the kilowatt level.

Main Results:

• Achieved a record output power exceeding 1.01 kW from an all-fiberized superfluorescent source.
• Maintained excellent beam quality with M(x)(2) = 1.688 and M(y)(2) = 1.728.
• Observed a central wavelength of 1074.4 nm with an 8.1 nm FWHM linewidth; demonstrated stable operation (<2% fluctuation) without self-pulsing.

Conclusions:

• Successfully demonstrated the first all-fiberized superfluorescent source with >1 kW output power.
• The MOPA configuration is effective for scaling superfluorescent sources to high power levels.
• Spectral evolution effects were investigated, providing insights for future high-power broadband fiber sources.