Holographic stability and storage capacity on bulk green-light sensitive TI/PMMA materials

An emerging cationic photo-initiator titanocene (TI) dispersed poly (methyl methacrylate) (PMMA) photopolymer was fabricated by an optimized three-step thermo-polymerization method with excellent holographic performances. Materials with different thicknesses (1-3 mm) were prepared and characterized experimentally. The influences of material thickness changes on holographic properties have been investigated in detail. We achieved the response time of 4.98s in 1mm TI/PMMAs, while the cumulative gratings strength of 6.88 and single grating diffraction efficiency of 74% in 3 mm ones. Furthermore, gratings recorded in materials were examined with controlling experimental conditions in a green-light two-beam coupling interference system, under different polarization directions, ambient temperatures and intersection angles, respectively. A better holographic recording condition was proposed. Meanwhile, the influence on recording surroundings for TI/PMMA were analyzed. This work can provide a basis to depict the holographic storage capacity and stability in TI/PMMA polymers.