Hybrid metal–semiconductor nanostructures unifying plasmonic and high-refractive-index materials in a single resonant system demonstrate a wide set of unique optical properties. Such systems are a perspective for a broad palette of applications, but the link between their inner structure and optical properties is a very sensitive issue, which is still not revealed. Here, we describe the influence of internal microstructure of a hybrid gold–silicon nanoparticle (the gold nanoparticle with embedded silicon nanograins) on the up-conversion white-light photoluminescence. The evolution in the internal microstructure of the system during thermal treatment up to 500 °C is tracked in situ through the HAADF and EDS STEM techniques. The studies show the redistribution of the materials inside the hybrid nanoparticle and the reduction of the silicon nanograin numbers under heating without an external modification of the nanoparticle shape. We have established numerically that the dependence of the enhancement factor spectral width on the S/V ratio of the nanoparticle plasmonic component is close to the linear behavior. The shrinkage of the photoluminescence spectrum (up to 42%) of the hybrid nanoparticle reconfigured by laser exposure and thermal treatment is shown experimentally, which supports our numerical conclusions. The results shed light on the connection of optical properties of complex hybrid systems with their complex internal composition, providing a powerful tool to control their optical properties through microstructure rearrangement. They also open the way to the development of reconfigurable silicon-based up-conversion light nanosources for integrated optical devices and biophotonics.

中文翻译：

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通过混合等离子体半导体纳米粒子的内部微结构控制在硅中进行上转换光致发光重构


混合金属-半导体纳米结构将等离子体和高折射率材料统一在一个谐振系统中，展示了一系列独特的光学特性。此类系统是广泛应用调色板的前景，但其内部结构和光学特性之间的联系是一个非常敏感的问题，至今仍未揭示。在这里，我们描述了混合金-硅纳米颗粒（嵌入硅纳米颗粒的金纳米颗粒）的内部微观结构对上转换白光光致发光的影响。在 500 °C 的热处理过程中，通过 HAADF 和 EDS STEM 技术原位跟踪系统内部微观结构的演变。研究表明，杂化纳米颗粒内部的材料重新分布，并且在加热时硅纳米颗粒数量减少，而纳米颗粒形状没有外部改性。我们已经从数值上确定，增强因子光谱宽度对纳米粒子等离子体成分的 S/V 比的依赖性接近线性行为。实验显示了通过激光曝光和热处理重新配置的混合纳米颗粒的光致发光光谱的收缩（高达 42%），这支持了我们的数值结论。结果揭示了复杂混合系统的光学特性与其复杂的内部组成之间的联系，为通过微观结构重排控制其光学特性提供了强大的工具。它们还为开发用于集成光学器件和生物光子学的可重构硅基上转换纳米光源开辟了道路。