Yellow laser of Dy³⁺ ions doped materials, has found various applications in Bose–Einstein condensation, visible light communication, medical treatment, and optical thermometry. Fluoride glasses are commonly used as host material for visible fiber due to their low-energy phonon distribution. Unfortunately, the difficulty of synthesis, poor mechanical strength, and degraded chemical stabilities limit their practical applications. As an alternative, silica fiber is well developed for fiber lasers owing to its advantages of optical, chemical and mechanical properties. Unfortunately, the output power in Dy³⁺-doped silica fiber was limited by the photodarkening

　　Most recently, a research team led by Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, has succeeded in strengthening photodarkening resistance of Dy³⁺ in silica glasses. The study was published in Journal of the American Ceramic Society. In their experiment, valence change of Dy ions and the formation of defects such as Al OHC from within the glass matrix caused by irradiation was inhibited by increasing the P/Al ratio.

　　Moreover, the introduction of P can form a valence equilibrium and stable [PAlO₄] structure with Al, which suppresses the formation of Al related defects and thus improves the photodarkening resistance of Dy doped silica glasses.

　　This research may lead to a host material for fiber laser operated at visible wavelength.

　　This work was supported by the National Natural Science Foundation of China.

　　  

　　Characterizations of Dy³⁺ doped silica glasses. 

　　Article website:

　　https://doi.org/10.1111/jace.19714