We demonstrate volume holographic recording at a wavelength of 640 nm in a photopolymerizable nanoparticle-polymer composite (NPC) film dispersed with ultrahigh refractive index hyperbranched-polymer (HBP) organic nanoparticles. We employ a new photosensitizer-initiator system consisting of cyanine dye, triazine compound and borate salt for efficient radical generation in the red. We investigate the electron transfer and radical generation processes of the system by measuring fluorescence quenching and photopolymerization dynamics to find the optimum composition of the system for volume holographic recording. We show that recorded volume gratings of 0.5-µm spacing possess the saturated peak-to-mean refractive index modulation amplitudes as large as 3×10⁻² at a readout wavelength of 640 nm. Our results show the usefulness of photopolymerizable HBP-dispersed NPCs for volume holographic recording materials for various photonic applications including security and color holograms, and volume Bragg grating devices in head-mounted displays.

中文翻译：

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用于具有大折射率调制幅度的体积全息光栅的红敏有机纳米颗粒-聚合物复合材料

我们展示了在分散有超高折射率超支化聚合物（HBP）有机纳米颗粒的可光聚合纳米颗粒-聚合物复合材料（NPC）膜中在640 nm波长处的体积全息记录。我们采用了一种由花青染料，三嗪化合物和硼酸盐组成的新型光敏引发剂体系，以有效地在红色中生成自由基。我们通过测量荧光猝灭和光聚合动力学来研究系统的电子转移和自由基生成过程，以找到用于体积全息记录的最佳系统组成。我们表明，记录的间距为0.5- μm的体光栅具有高达3×10 ^-2的饱和峰均折射率调制幅度在640 nm的读出波长下。我们的结果表明，可光聚合的HBP分散NPC可用于各种全息应用的体积全息记录材料，包括安全和彩色全息图以及头戴式显示器中的体积布拉格光栅设备。