The perfectly matched layer (PML) technique is a general-purpose absorbing boundary condition for finite methods which is usually applied within explicit time-domain schemes. There are a number of slightly different implementations of the extended update equations, and many of them have been reported in the literature to show some long-term instabilities, typically only weakly depending on the time step size. In this contribution, we present a hybrid implicit–explicit algorithm that introduces two additional parameters to control the stability. The implicit part of the algorithm is used only locally within the PML region, and for a simple setup, stability is reached for a certain range of the additional parameters.

中文翻译：

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使用混合隐式-显式更新方案研究完美匹配层实现的稳定性

完美匹配层 (PML) 技术是有限方法的通用吸收边界条件，通常应用于显式时域方案。扩展更新方程有许多略有不同的实现，其中许多已在文献中报告，以显示一些长期不稳定性，通常仅微弱地取决于时间步长。在这个贡献中，我们提出了一种混合隐式-显式算法，它引入了两个额外的参数来控制稳定性。该算法的隐式部分仅在 PML 区域内局部使用，并且对于简单的设置，对于一定范围的附加参数达到稳定性。