单分子信息存储和动态防伪研究

Surface plasmon coupling induced localized electromagnetic field enhancement between two metal (plasmonic) nanostructures has great potential applications in nanoscale optoelectronics and single-molecule optoelectronics. Single molecule fluorescence blinking is the unique phenomenon of single molecule optics. The blinking molecule is considered as an ideal element of binary data storage that can dynamically hold either 1 (bright status) or 0 (dark status). The design and fabrication of normal fluorescence microscope detectable, surface-plasmon-enhanced single molecule fluorescence information carriers is the key to the development of dynamic security labels. This project aims to develop a smart-phone readable, nanoparticle fingerprint coded, dynamic anti-counterfeiting technology. Dye-embedded metal/silica core-shell nanoparticles will be used as building blocks for the self-assembly of dynamic fluorescence information carriers that are made of the core-shell nanoparticles coupled metal film. We will systematically investigate the relationship between the information carrier’s structure and surface-plasmon-enhanced fluorescence of single dye molecules, and unveil the interaction mechanism between plasmonic nanostructures and single fluorescence molecules. We will also explore new nanoparticle fingerprint coding techniques to pattern dynamic information carriers. It is expected that the findings in this research would provide useful information for understanding single molecule optical information storage and would be helpful for the design and fabricate of dynamic security labels.

表面等离子体耦合引起的局域电磁场增强效益在纳米光电学和单分子光电学领域有广泛的应用前景。单分子荧光闪烁是单分子光学的独特现象，其闪烁过程就是动态随机存储1（亮状态）和0（暗状态）两种信息的过程。因此，被视为理想的动态光学信息基元。构建可普通荧光显微镜识别的、表面增强单分子荧光动态信息基元是研发动态防伪标签必须解决的关键问题。本项目以发展可智能手机验证的、亚波长光学动态指纹防伪技术为总目标，以包裹染料分子的金属/二氧化硅核壳纳米颗粒为组成单元，自组装的核壳纳米颗粒－金属薄膜耦合体系为动态光学信息基元，系统研究信息基元结构与表面增强单分子荧光性质间的关系，揭示金属纳米结构与荧光单分子间相互作用规律，探索动态信息基元指纹图案加密技术，为单分子光学信息存储与动态指纹防伪奠定理论基础和提供技术源头。

表面等离子体耦合引起的局域电磁场增强效应在纳米光电学和单分子/单颗粒光电学领域有广泛的应用前景。荧光闪烁是单分子或单颗粒量子点光学的独特现象，其闪烁过程就是动态随机存储1（亮状态）和0（暗状态）两种信息的过程。因此，被视为理想的动态光学信息基元。本项目主要构建了表面增强单分子染料荧光闪烁体系和单颗粒钙钛矿量子点荧光闪烁体系， 即（1）以包裹染料分子的金属/二氧化硅核壳纳米颗粒为组成单元，自组装的核壳纳米颗粒－金属薄膜耦合体系为动态光学信息基元，系统研究了信息基元结构与表面增强单分子荧光性质间的关系；（2）以包裹在PMMA中的全无机钙钛矿量子点为信息单元，系统研究了量子点的光学稳定性，热稳定性，以及单量子点光学性质。首次实现了无相干光源激发的，普通荧光显微镜可视的表面等离激元增强单分子荧光闪烁，并揭示了该现象是由热点区域的电磁场增强效应和Purcell效应协同作用引起的；此外，也首次实现了无相干光源激发的，智能手机可视的单颗粒量子点荧光闪烁。获得长时间化学稳定和光学稳定的荧光闪烁（动态）防伪和信息加密器件。开发了动态光学信息基元指纹图案加密与解密技术，为单分子和单量子点光学信息存储与动态指纹防伪奠定理论基础和提供技术源头。