We develop a theoretical model of the excitation and interference of surface plasmon polariton (SPP) waves with femtosecond laser pulses and use the model to understand the features in images from subfemtosecond time-resolved two-photon photoelectron microscopy (2PPE–PEEM). The numerically efficient model is based on the optics of SPP modes on multilayer thin films and takes account of the excitation and interference by the incident light, its polarization, the boundary shape on the film where the plasmons are generated, the pulsed form of the excitation and the time integration associated with the PEEM method. The model explains the dominant features observed in the images including the complex patterns formed in experiments involving orbital angular momentum. The model forms the basis of an efficient numerical method for simulating time-resolved 2PPE–PEEM images of SPP wave propagation. The numerics is extremely fast, efficient, and accurate, so that each image can take as little as a few seconds to calculate on a laptop computer, enabling entire PEEM movies to be calculated within minutes.

中文翻译：

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亚飞秒和纳米等离激元动力学的光电子显微镜：理论和有效的模拟

我们建立了飞秒激光脉冲对表面等离子体激元（SPP）波的激发和干扰的理论模型，并使用该模型来了解飞秒时间分辨的两光子光电子显微镜（2PPE-PEEM）的图像特征。数值有效的模型基于多层薄膜上的SPP模光学，并考虑了入射光的激发和干扰，其偏振，产生等离子体激元的膜的边界形状，激发的脉冲形式以及与PEEM方法相关的时间积分。该模型解释了在图像中观察到的主要特征，包括在涉及轨道角动量的实验中形成的复杂图案。该模型构成了一种有效的数值方法的基础，用于模拟SPP波传播的时间分辨2PPE–PEEM图像。这些数字非常快速，高效和准确，因此在便携式计算机上计算每个图像只需几秒钟，从而可以在数分钟内计算出整个PEEM电影。