多元复合型纳米间隙阵列的构筑及其光学应用

Nanogaps could bring enormous electromagnetic (EM) field enhancement and strong confinement of the optical field. With a further decrease in gap size, the strength of EM coupling increases sharply, leading to a rapidly increased field enhancement in the gap, which is very important for optical/electrical detection and sensing. Here, aiming at the problem of limited fabrication methods with high cost but low yield in nanogap area, taking advantage of modified colloidal lithography on building nanostructures along the Z-axis perpendicular to the substrate, we adjust the gap size by controlling the deposition process to fabricate nanogaps with precise control of the gap’s size, position, shape and orientation. Moreover, the substrate-dependence problem can be solved fundamentally due to the unique transfer method of nanoskiving. Combination with nanoskiving’s characteristic of continuous sectioning, to break the unicity of traditional nanogap structures, nanogaps could be assembled as building blocks into three-dimensional multi-composite nanogap arrays, to excite unique plasmon resonance in the fresh nanogap arrays. Thus, multi-heterostructure and multi-composite functional nanogaps can be successfully constructed, and then exploring their applications in physical chemical and biological detection and chiral molecule resolution could be possible.

纳米间隙结构可产生明显的电磁场增强，并对光场具有很高的限域性。随着间隙尺寸的减小电磁场强度急剧增强，使得纳米间隙在光学、电学检测和传感领域都有着重要应用。针对目前纳米间隙领域制备方法局限，以及能耗高、产率低等问题，本项目首先利用改性胶体刻蚀，发挥其在垂直于基底方向上灵活构筑结构的优势，通过控制宏观沉积过程来调控微观间隙的尺寸（小于10 nm），制备形状与尺寸精确可控的纳米间隙结构。进一步利用纳米切割技术独特的转移方式，从根本上解决传统纳米间隙基底依赖问题。结合纳米切割可连续切片的特点，打破传统纳米间隙结构的单一性，将纳米间隙作为组装单元进一步组装形成三维、多元、复合的纳米间隙阵列，激发新型纳米间隙结构中特殊的等离子体共振模式，实现不同材料、不同形状的多元异质复合结构等多功能集成纳米间隙的构筑，进而探索这种复合的纳米间隙阵列结构在物理化学与生物检测、手性分子鉴别和拆分等领域的深入应用。

纳米间隙结构可产生显著的电磁场增强，并对光场具有很高的限域性。随着间隙尺寸的减小电磁场强度急剧增强，使得纳米间隙在光学、电学检测和传感领域都有着重要应用。针对目前纳米间隙领域制备方法局限，以及能耗高、产率低等问题，本项目利用改性胶体刻蚀及其衍生的刻蚀方法，发挥其在垂直于基底方向上灵活构筑结构的优势，通过可控沉积过程来调控微观间隙的尺寸（小于10 nm），制备形状与尺寸精确可控的纳米间隙结构。进一步利用纳米切割技术独特的转移方式，从根本上解决传统纳米间隙基底依赖问题。结合纳米切割可连续切片的特点，打破传统纳米间隙结构的单一性，将纳米间隙作为组装单元进一步组装形成三维、多元、复合的纳米间隙阵列，激发新型纳米间隙结构中特殊的等离子体共振模式，实现不同材料、不同形状的多元异质复合乃至具有手性特征结构等多功能集成纳米间隙的构筑，进而探索这种复合的纳米间隙阵列结构在物理化学与生物检测、手性分子鉴别和拆分等领域的深入应用。