Near-Field Scanning Optical Spectroscopy: Localized Fluorescence Spectra of Clusters in Nd³⁺ Doped Polymer Optical Fibre

The optical characteristics of fractal clusters in Nd³⁺ doped poly(methyl and methacrylate) (PMMA) are investigated. The localized fluorescence spectra of clusters in Nd³⁺ doped PMMA are detected with a near-field scanning optical microscope. The experimental results demonstrate that the fractal clusters are harmful to the polymer optical fibre laser and amplifier. The corresponding explanation shows that there are interactions between two adjacent Nd³⁺ ions.