Spatial frequency-dependent polarization holography in TI/PMMA photopolymers for high-density storage

This study presents a systematic investigation of orthogonal polarization holographic storage in titaniumocene-doped poly (methyl methacrylate) (TI/PMMA) photopolymers, focusing on spatial frequency dependencies (328-3760 lines/mm) and their interplay with holographic performance. By unifying Maxwell's equations with third-order dielectric tensor analysis, we developed a predictive theoretical framework to resolve the non-monotonic relationship between spatial frequency, diffraction efficiency (<i>η</i>), and refractive index modulation (Δ<i>n</i>). Experimental results demonstrate a maximum Δ<i>n</i> of 1.29 × 10^-4 alongside a stable diffraction efficiency of 42% (1500 lines/mm, 50 ° incident intersection angle) and a record-low response time of 80.2 s at 3760 lines/mm. Notably, the material exhibits exceptional polarization fidelity, with polarization conversion ratios (PCR) exceeding 94% across thicknesses (1-3 mm) and exposure energies (10-30 mW). These findings provide a detailed research foundation for the polarization holographic storage of TI/PMMA polymer materials and offer feasibility and potential for high-density data storage of wavefront phase, polarization, and amplitude information simultaneously in the future.