Ytterbium-Phosphate Glass for Microstructured Fiber Laser

Area of Science:

• Materials Science
• Optoelectronics
• Laser Physics

Background:

• Phosphate glasses are crucial for manufacturing active microstructured optical fibers.
• Developing novel glass compositions with tailored optical and thermal properties is essential for advanced fiber lasers.

Purpose of the Study:

• To synthesize and characterize novel phosphate glasses for active microstructured fiber fabrication.
• To develop Ytterbium-doped (Yb2O3) phosphate glass fibers for laser applications.
• To evaluate the performance of a laser built with the developed fiber.

Main Methods:

• Synthesis and melting of a P₂O₅-Al₂O₃-BaO-ZnO-MgO-Na₂O based phosphate glass matrix.
• Doping the glass matrix with 6 mol% Yb₂O₃ for the fiber core.
• Characterization of optical (refractive index) and thermal (thermal expansion coefficient, rheology) properties.
• Fabrication of microstructured optical fibers with Yb³⁺-doped core and air-cladding.
• Construction and testing of a laser cavity using the fabricated fiber.

Main Results:

• The synthesized phosphate glasses exhibited suitable optical and thermal properties for fiber manufacturing.
• Microstructured optical fibers with an Yb³⁺-doped core and high relative hole size in the air-cladding were successfully produced.
• The fiber laser achieved 8.07 W output power with 20.5% slope efficiency.
• Single-mode operation with M² = 1.59 was demonstrated in a 53 cm-long cavity.

Conclusions:

• The developed phosphate glass matrix and Yb³⁺-doped fiber are suitable for high-power laser applications.
• The fabrication method enables the creation of microstructured fibers with specific optical and thermal characteristics.
• The results demonstrate the potential of these novel fibers for efficient laser operation.