By incorporating the higher-order concept with the perfectly matched later (PML) scheme, unconditionally stable approximate Crank–Nicolson algorithm is proposed for plasma simulation in open region problems. More precisely, the proposed implementation is based on the CN Direct-Splitting (CNDS) procedure for the finite-difference time-domain (FDTD) unmagnetized plasma simulation. The unmagnetized plasma can be regarded as frequency-dependent media which can be calculated by the piecewise linear recursive convolution (PLRC) method. The proposed implementation shows the advantages of higher-order concept, CNDS procedure, and PLRC method in terms of improved absorbing performance, enhanced computational efficiency, and outstanding calculation accuracy. Numerical examples are introduced to indicate the effectiveness and efficiency. It can be concluded from results that the proposed scheme shows considerable efficiency, accuracy, absorption, and unconditional stability.

中文翻译：

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近似Crank-Nicolson算法的高阶PML实现，用于开放区域问题的等离子体仿真

通过将高阶概念与稍后完全匹配（PML）方案相结合，提出了无条件稳定的近似Crank-Nicolson算法，用于在开放区域问题中进行等离子体模拟。更准确地说，所提出的实施方案是基于CN直接分离（CNDS）程序的，用于有限差分时域（FDTD）非磁化等离子体仿真。未磁化的等离子体可视为频率相关的介质，可以通过分段线性递归卷积（PLRC）方法计算得出。所提出的实现方案在提高吸收性能，提高计算效率和出色的计算精度方面显示了高阶概念，CNDS程序和PLRC方法的优点。通过数值算例说明有效性和效率。