Enhanced broadband NIR emission in glass–ceramic fibers containing Nd3+/Yb3+ co‐doped YCa4O(BO3)3 disordered nanocrystal.

Demands are increasing for ultrashort pulse laser in industrial applications, where the gain bandwidth of most optical fiber material is not wide enough, and developing a wide bandwidth gain medium is challenging. Glass–ceramic fibers containing Nd3+/Yb3+ co‐doped YCa4O(BO3)3 nanocrystals were fabricated by the molten core method and successive heat treatment. After a careful heat treatment, Nd3+/Yb3+ co‐doped YCa4O(BO3)3 nanocrystals were precipitated in the fiber core. Enhanced broadband near‐infrared (NIR) emission from 850 to 1150 nm (bandwidth: ∼252 nm) was obtained in the glass–ceramic fiber compared to that of precursor fiber. These results suggest that the Nd3+/Yb3+ glass–ceramic fibers are promising for broadband NIR optical amplifications and lasers. [ABSTRACT FROM AUTHOR]