Lanthanide composite as doping reagent simplifies and uniformizes deposition of fiber preforms

Controlling the volatilization and diffusion of co-dopants to afford the uniform distribution of co-doping lanthanide elements with appropriate concentration is crucial to ytterbium (Yb)/erbium (Er) co-doped fiber preforms. Here, volatile and thermostable lanthanide composite Yb0.95Er0.05(thd)3 is proposed and demonstrated to practicably regulate the doping concentration by the fixed Yb/Er molar ratio in the formation, suitable for continuous deposition with simply one raw material transfer line for both Yb and Er elements. Benefiting from more uniform distributions and higher Yb→Er energy transfer efficiency, stronger ErIII-based emission of the Er/Yb co-doped fiber preforms prepared with Yb0.95Er0.05(thd)3 than that with traditional Yb(thd)3/Er(thd)3 is achieved. This work highlights the advantage of this lanthanide composite as a doping reagent in simplifying and uniformizing the deposition of lanthanide-doped fiber preforms, and it establishes the relationship between the doping reagent at molecular levels and the performance of fiber preforms. [Display omitted] •A lanthanide composite is proposed for doping fiber preforms•Yb0.95Er0.05(thd)3 with better sublimation performance and suitable for deposition•The deposition is simplified with one transmission line•Co-doping elements are uniformly dispersed into the fiber preforms Huang et al. propose a lanthanide composite as the doping reagent for fiber preforms. It not only simplifies the deposition process by only one raw material transfer line, but it also uniformly disperses both Yb and Er elements into the fiber preforms, affording more pronounced ErIII-based emission than the traditional reagents with similar content.