Title: Geometry Dependent Localization of Surface Plasmons on Random Gold Nanoparticle Assemblies Show Chinese title

Title: 几何依赖的随机金纳米颗粒组装体表面等离激元的局域化

Abstract: Assemblies of plasmonic nanoparticles (NPs) support hybridized modes of localized surface plasmons (LSPs), which delocalize in geometrically well-ordered arrangements. Here, the hybridization behavior of LSPs in geometrically completely disordered arrangements of Au NPs fabricated by an e-beam synthesis method is studied. Employing electron energy loss spectroscopy in a scanning transmission electron microscope in combination with numerical simulations, the disorder-driven spatial and spectral localization of the coupled LSP modes that depend on the NP thickness is revealed. Below 0.4 nm sample thickness (flat NPs), localization increases towards higher hybridized LSP mode energies. In comparison, above 10 nm thickness, a decrease of localization (an increase of delocalization) with higher mode energies is observed. In the intermediate thickness regime, a transition of the energy dependence of the localization between the two limiting cases, exhibiting a transition mode energy with minimal localization, is observed. This behavior is mainly driven by the energy and thickness dependence of the polarizability of the individual NPs. Show Chinese abstract

Abstract: 等离子纳米颗粒（NPs）的组装支持局域表面等离子体（LSPs）的杂化模式，这些模式在几何上有序排列时会扩展。 在这里，研究了通过电子束合成方法制备的金纳米颗粒（Au NPs）几何上完全无序排列中LSPs的杂化行为。 采用扫描透射电子显微镜中的电子能量损失谱结合数值模拟，揭示了耦合LSP模式的由无序驱动的空间和光谱局域化，这种局域化取决于纳米颗粒的厚度。 在0.4纳米以下样品厚度（平坦纳米颗粒）时，局域化随着更高杂化LSP模式能量的增加而增加。 相比之下，在10纳米以上的厚度下，观察到随着模式能量的增加，局域化减少（即扩展性增加）。 在中间厚度范围内，观察到两种极限情况之间局域化能量依赖性的转变，表现出具有最小局域化的过渡模式能量。 这种行为主要由单个纳米颗粒的极化率的能量和厚度依赖性驱动。