Tm/Al Co-Doped Silica Glass Prepared by Laser Additive Manufacturing Technology for 2-μm Photonic Crystal Fiber Laser

In this article, we demonstrated the Tm/Al co-doped silica glass fabricated by the laser additive manufacturing technology for the first time. The measurements show that the glass was doped with Tm
³⁺
concentration of 1.64 wt% without any crystallization. The Tm
³⁺
and Al
³⁺
were uniformly distributed, and no additional defects were introduced during the fabrication process. The glass exhibits low hydroxyl content level of 11.56 ppm. Using the prepared silica glass as the core rod, a Tm/Al co-doped photonic crystal fiber (PCF) was fabricated and performed 13.9% slope efficiency with nearly 600 mW output laser power. This novel technology provides an alternative method to fabricate Tm-doped fiber materials with high homogeneity and large core size, promoting the further spread and development of 2 μm fiber lasers.