A staggered-grid high-order difference method of complex frequency-shifted PML based on recursive integration for elastic wave equation
基于递归积分的复频移PML弹性波方程交错网格高阶差分法

The classical PML algorithm will make spurious reflection for the waves being incident on the PML interface at near-grazing angles and the evanescent waves within PML. We adopt a nonsplit complex frequency-shifted PML method based on recursive integration, which includes the complex frequency-shifted stretching function and substantially improves the performance of the PML boundary condition. Furthermore, we derive a nonsplit staggered-grid higher-order difference method of complex frequency-shifted PML based on recursive integration for elastic wave equation. Compared to the classical PML, the results of models with an elongated domain show the absorption performance to both body waves with grazing incidence and evanescent waves within PML.