In order to demonstrate acceleration of electrons to relativistic scales by an on chip dielectric laser accelerator (DLA), a ponderomotive focusing scheme capable of capturing and transporting electrons through nanometer-scale apertures over extended interaction lengths has been proposed. We present a Matlab-based numerical code (SHarD) utilizing a spatial harmonic expansion of the fields within the dielectric structure to simulate the evolution of the beam phase space distribution in this scheme. The code can be used to optimize key-parameters for the accelerator performance such as the final energy, transverse spot size evolution and total number of electrons accelerated through currently fabricated structures. Eventually, the simulation model will be applied to inform the phase mask profile to be added to a pulse front tilt drive laser pulse using a liquid crystal mask in the experimental setup being assembled at UCLA Pegasus Laboratory.

为了证明通过片上介电激光加速器 (DLA) 将电子加速到相对论尺度，已经提出了一种能够在扩展的相互作用长度上通过纳米级孔径捕获和传输电子的有质聚焦方案。我们提出了一种基于 Matlab 的数值代码 (SHArD)，利用介电结构内场的空间谐波扩展来模拟该方案中束相空间分布的演变。该代码可用于优化加速器性能的关键参数，例如最终能量、横向光斑尺寸演变和通过当前制造的结构加速的电子总数。最终，