Characterization of Clusters in a Novel Nd³⁺-Doped Polymer Optical Fiber

A step index-type Nd³⁺-doped polymer optical fiber (POF) was prepared by using bulk polymerization of solution of Nd³⁺-octanoate (NOA) and methyl and methacrylate. A method of wide-angle x-ray diffraction was used to measure the solubility of NOA. In a high concentration Nd³⁺ doped POF, a residual absorption at 810nm could not be saturated, which is attributed to the high clustered ion rate in the Nd³⁺ POF. A model based on the rate equations to infer the clustered ion rate by the measurement of transmission is presented.