By incorporating the higher order concept, the piece-wise linear recursive convolution (PLRC) method and Crank-Nicolson Douglas-Gunn (CNDG) algorithm, the unconditionally stable complex frequency shifted nearly perfectly matched layer (CFS-NPML) is proposed to terminate the left-handed material (LHM) domain. The proposed scheme takes advantages of CFS-NPML formulation, the higher order concept PLRC method and the unconditionally stable CNDG algorithm in terms of absorbing performance, computational efficiency, calculation accuracy and convenient implementation. A numerical example is carried out to demonstrate the effectiveness and efficiency of the proposed scheme. The results indicate that the proposed scheme can not only have considerable absorbing performance but also maintain the unconditional stability of the algorithm with the enlargement of time steps.

中文翻译：

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左手物料的高阶隐式CNDG-PML算法

通过结合高阶概念，分段线性递归卷积（PLRC）方法和Crank-Nicolson Douglas-Gunn（CNDG）算法，提出了无条件稳定的复杂频移几乎完美匹配层（CFS-NPML）来终止左手材料（LHM）域。该方案在吸收性能，计算效率，计算精度和实现方便性方面都利用了CFS-NPML公式，高阶概念PLRC方法和无条件稳定的CNDG算法。数值算例表明了所提方案的有效性和有效性。