Praseodymium-doped clusters of chloride in silica: a new 1.3 um light amplifying material

摘要

Praseodymium-doped fluoride fiber amplifiers (PDFA) for 1.3 $mu@m light will approach their practical applications to information superhighway if many outstanding device performance issues can be satisfactorily resolved. Efforts have been made to fabricate high quality praseodymium-doped fluoride fibers with a large NA (0.4), a low background loss (0.05 dB/m), a median strength (4%), and a good slope quantum efficiency (50%). Even better parameters are desired. Mixed halide glasses are studied as more efficient hosts for praseodymium. In this paper we propose an approach to combine the advantages of chloride in offering a good light amplifying environment for Pr$+3$PLU$/ ions with the advantages of silica in offering good chemical protection and mechanical support to the chloride to make a new nanostructured material for 1.3 $mu@m light amplifiers. In this approach praseodymium-doped chloride glass clusters of 10 nm sizes are compounded in silica host. In addition to the advantages of the composite material the gradient distribution of the clusters from the center and along one dimension of the composite material may result in the weldability of the material with the traditional silica fibers, which is preferable in engineering practice. Primitive samples were made and characterized.