All-fiber core-pumped Ho-doped laser with 95 W output power and high efficiency

Area of Science:

• Laser Physics
• Photonics
• Materials Science

Background:

• Fiber lasers offer compact and efficient solutions for various applications.
• Holmium-doped fiber lasers (HDFLs) operating in the 2.1 µm spectral region are of significant interest.
• Achieving high output power from HDFLs requires optimized pumping and fiber architectures.

Purpose of the Study:

• To develop and characterize a core-pumped, all-fiber, monolithic holmium-doped silica fiber laser (HDFL).
• To investigate the performance of a HDFL pumped by a high-power thulium-doped fiber laser at 1940 nm.
• To demonstrate high continuous-wave output power and efficiency for 2.1 µm fiber laser sources.

Main Methods:

• Utilized a core-pumped, all-fiber, monolithic holmium-doped silica fiber laser (HDFL) architecture.
• Employed a high-power thulium-doped fiber laser operating at 1940 nm as the pump source.
• Conducted experiments to measure output power and slope efficiency, supported by numerical modeling for power scaling.

Main Results:

• Achieved up to 95 W of continuous-wave output power at 2109 nm.
• Obtained a slope efficiency of 84% with respect to launched pump power, a 10% improvement over previous studies.
• Demonstrated the effectiveness of core pumping with advanced thulium-doped fiber laser architectures.

Conclusions:

• The developed core-pumped HDFL represents a significant advancement in high-power fiber laser technology.
• The results highlight the potential of compact and efficient Ho-doped fiber sources for high-power applications in the 2.1 µm region.
• Numerical modeling suggests further power scaling capabilities up to 250 W are feasible.