Effect of ZnMA on Optical and Holographic Characteristics of Doped PQ/PMMA Photopolymer

Abstract

We report on the fabrication and experimental characteristics of doping Zinc methylacrylate (ZnMA) and 9,10-phenanthrenequinone (PQ) into a poly(methyl methacrylate) (PMMA) photopolymer. The effects of a ZnMA dopant on the optical and holographic characteristics of ZnMA/PQ/PMMA have been examined. From the optical and holographic measurements of different samples with different composition ratios, we found that the time to reach the maximum diffraction efficiency has been reduced from 102 to 59 (reduced by 1.7 times) and the diffraction efficiency has been raised up from 0.57 to 1.62% (increased by 2.9 times). We also found that holographic gratings can be recorded in pure PQ-doped PMMA, but cannot be recorded in pure ZnMA-doped PMMA. The higher the concentration of PQ in codoped PMMA, the higher the diffraction efficiency. In contrast, the higher ZnMA concentration in the codoped PMMA, the shorter the response time. It is proposed that PQ serves as a photosensitive reactant and plays a major role in the formation of phase gratings. ZnMA serves as a sufficient catalyst to accelerate the reaction of PQ with a polymer or ZnMA. By adding ZnMA with a proper concentration into a PQ/PMMA photopolymer, we succeeded in improving the holographic characteristic of the photopolymer.