Silicate-clad highly Er3+/Yb3+ co-doped phosphate core multimaterial fibers

Highly rare earth ions (RE-ions) doping phosphate glass fiber makes it possible to obtain high gain and high output power per unit length. However, high concentrations of RE-ions will cause concentration quenching and crystallization during the conventional rod-in-tube fiber drawing process. In this work, highly Er3+/Yb3+ co doped multi-component phosphate glasses were prepared by the melt-quenching method. Through thorough investigation of 1.53 mu m luminescent properties of the glasses, optimal RE-ions were ascertained. The Er3+ and Yb3+ doping concentrations reach as high as 13.77 x 10(20) and 2.295 x 10(20) ions/cm(3), respectively. Then the silicate-clad highly Er3+/Yb3+ co-doped phosphate core multimaterial fibers were successfully fabricated by a molten core method. The multimaterial fibers have a large refractive index difference and good interface between the phosphate glass core and silicate glass cladding. An intense 1.53 pm emission was obtained from the multimaterial fiber. The results indicate that the highly Er3+/Yb3+ co-doped multimaterial fibers are promising in applications that require high gain and high power from a short piece of active optical fiber. (C) 2016 Elsevier B.V. All rights reserved.