Nonlocal effects have been shown to be responsible for a variety of nontrivial optical effects in small-size plasmonic nanoparticles, beyond classical electrodynamics. However, it is not clear whether optical mode descriptions can be applied to such extreme confinement regimes. Here, we present a powerful quasinormal mode description of the nonlocal optical response for three-dimensional plasmonic nanoresonators. The nonlocal hydrodynamical model and a generalized nonlocal optical response model for plasmonic nanoresonators are used to construct an intuitive modal theory and to compare to the local Drude model response theory. Using the example of a gold nanorod, we show how an efficient quasinormal mode picture is able to accurately capture the blueshift of the resonances, the higher damping rates in plasmonic nanoresonators, and the modified spatial profile of the plasmon quasinormal modes, even at the single mode level. We exemplify the use of this theory by calculating the Purcell factors of single quantum emitters, the electron energy loss spectroscopy spatial maps, and the Mollow triplet spectra of field-driven quantum dots with and without nonlocal effects for different size nanoresonators. Our nonlocal quasinormal mode theory offers a reliable and efficient technique to study both classical and quantum optical problems in nanoplasmonics.

中文翻译：

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任意形状的三维等离激元谐振器的非局部拟正态模

已经证明，非局部效应是造成小尺寸等离子体纳米粒子中多种非平凡光学效应的原因，这超出了经典的电动力学。但是，尚不清楚是否可以将光学模式描述应用于此类极端限制制度。在这里，我们提出了三维等离激元纳米谐振器的非局部光学响应的​​强大准正规模式描述。等离子体激元谐振器的非局部流体动力学模型和广义非局部光学响应模型用于构建直观的模态理论，并与局部Drude模型响应理论进行比较。以金纳米棒为例，我们展示了高效的准法向模式图片如何能够准确捕获共振的蓝移，等离激元纳米共振器的较高阻尼率，以及等离激元准正态模态的修改后的空间分布，即使在单模态水平也是如此。我们通过计算单个量子发射体的赛尔因数，电子能量损失谱空间图以及场驱动量子点的Mollow三重态谱来举例说明此理论的使用，该场驱动的量子点具有和不具有针对不同尺寸的纳米谐振器的非局域效应。我们的非局部准正规模理论提供了一种可靠而有效的技术，可以研究纳米等离激元学中的经典和量子光学问题。以及场驱动量子点的Mollow三重态光谱，该量子点对于不同尺寸的纳米谐振器具有和不具有非局部效应。我们的非局部准正规模理论提供了一种可靠而有效的技术，可以研究纳米等离激元学中的经典和量子光学问题。以及场驱动量子点的Mollow三重态光谱，该量子点对于不同尺寸的纳米谐振器具有和不具有非局部效应。我们的非局部准正规模理论提供了一种可靠而有效的技术，可以研究纳米等离激元学中的经典和量子光学问题。