Toward 10 W-level all-fiber multi-color visible lasers

Area of Science:

• Optics and Photonics
• Materials Science

Background:

• High-power visible lasers traditionally use nonlinear frequency conversion, which is inefficient and costly.
• Rare-earth-doped fiber lasers offer a potential solution but are limited in power and rarely all-fiber.

Purpose of the Study:

• To demonstrate high-power, all-fiber visible lasers for direct generation of visible light.
• To overcome the limitations of existing visible laser technologies.

Main Methods:

• Theoretical optimization and experimental validation of a 443 nm LD-pumped Pr³⁺-doped double-clad fiber laser.
• Utilized self-designed, homemade visible fiber dichroic mirrors with a high damage threshold (>22.6 MW/cm²).

Main Results:

• Achieved 10 W-level output power for red (635 nm) and deep-red (717 nm) lasers, and 5 W-level for green (521 nm) lasers.
• Maximum output powers reached 10.34 W (635.6 nm), 10.28 W (717.2 nm), and 4.87 W (521.4 nm) with slope efficiencies of 26.5%, 24.4%, and 21.4%, respectively.
• Demonstrated excellent laser stability with low power fluctuations (0.93%, 0.33%, 2.8%).

Conclusions:

• This work presents the highest visible continuous-wave (CW) output power directly generated from a compact all-fiber laser.
• Represents a significant advancement towards practical, high-power all-fiber visible laser systems.