Effect of thermal polymerization temperature and time of PQ/PMMA on the holographic data storage

Abstract

Phenanthraquinone-doped polymethylmethacrylate (PQ/PMMA) photopolymer is a promising material for holographic data storage, according to the negligible shrinkage, polarization sensitivity, and easy preparation. In this paper, we investigated the effect of thermal polymerization temperature and time of PQ/PMMA on the collinear holographic data storage system. By designing the baking temperatures 50℃ and 60℃ and baking times 4-20 hours each 2 hours during thermal polymerization. The information page storage and representation results show that under the baking temperature of 50℃ when the baking times were less than 8 hours, the material could not record the data page, and the bit error rate (BER) of the reconstructed data page was increased with the baking time extension. The material baked for 10 hours recorded data with the best results and reconstructed data pages with a minimum BER of 1.5%, when the baking time is 20 hours, the BER of the reconstructed data page was increased by about 12% compared to the baking time of 10 hours. When the baking temperature is 60℃, the data page BER was also increased with the baking time extension except for a very short baking time within 2.5 hours. We analyze the molecular weight of these materials that can be changed by controlling the baking temperature and time of thermal polymerization properly so that grating generation and readout efficiency can be changed. We believe the analysis is useful for the application of PQ/PMMA on collinear holographic data storage.