Over the last few decades, dielectric core and metallic plasmonic shell (Die@Me) nanoparticles have found a wide variety of applications. The trend to reduce the thickness of the metallic coating requires to account for the influence of the nonlocal dispersion on the spectral response of such nanoparticles. In this paper, we use the discrete sources method and the generalized nonlocal optical response model to describe the nonlocality within the plasmonic metal shell. We found that the variation of the plasmonic shell thickness and the elongation of the nonspherical core-shell particle can enlarge the near-field enhancement and the absorption cross section by an order of magnitude. Besides, we show that the nonlocal dispersion can decrease the field enhancement in the wavelength domain up to 2.5 times with a small blue-shift of about 5 nm.

中文翻译：

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分析非球形介质核金属壳颗粒近场增强的数值方法，解释了非局部色散。

在过去的几十年中，介电核和金属等离激元壳（Die @ Me）纳米粒子已发现了各种各样的应用。减小金属涂层厚度的趋势需要考虑非局部分散对这种纳米颗粒的光谱响应的影响。在本文中，我们使用离散源方法和广义的非局部光学响应模型来描述等离激元金属壳内的非局部性。我们发现等离激元壳厚度的变化和非球形核-壳粒子的伸长率可以将近场增强和吸收截面扩大一个数量级。此外，我们表明，非局部色散可以在约5 nm的小蓝移下，将波长域的场增强降低至2.5倍。