The clusters of Eu^(3+) ion in Eu(DBM)3Phen-doped polymethyl methacrylate (PMMA) have been studied by three means. The relative fluorescence intensity ratio of the 5D0 -> 7F2 to 5D0 -> 7F1 transitions with different concentrations of Eu^(3+) in Eu(DBM)3Phen-doped PMMA and metastable-state (5D0) lifetime dependence on Eu^(3+) concentration are analyzed. The analysis indicates that there are no clustering effects in Eu^(3+) ions of Eu(DBM)3Phen-doped PMMA when the Eu^(3+) doping concentration is up to 1.0 wt.-%. At the same time, the clustering effect has not been observed by the scanning near-field optical microscopy (SNOM) in Eu(DBM)3Phen-doped PMMA with 1.0 wt.-% of Eu^(3+) ions. The analysis reveals that a high concentration of Eu^(3+) can be incorporated into polymer optical fiber (POF) without clustering effect.

A four-channel 400-GHz spacing flat focal field arrayed waveguide grating (AWG) demultiplexer is designed based on polymeric optical waveguide. The waveguide core-layer material is a newly developed negative tone epoxy Novolak resin (ENR) polymer with ultravoilet (UV) cured resin Norland optical adhesive 61 (NOA61) as the cladding layer. The device is fabricated using electron-beam direct writing, which has less processing steps than the reported polymeric AWGs. The experimental result is presented.