Concentration-dependent /sup 4/I/sub 13/2/ lifetimes in Er/sup 3+/-doped fibers and Er/sup 3+/-doped planar waveguides

We report on the concentration- and pump-dependent lifetimes of the spontaneous emission in Er/sup 3+/-doped fibers and Er/sup 3+/-doped waveguides. In addition, we measure the concentration dependence of the 550-nm fluorescence due to excited state absorption (ESA).<
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