A novel and efficient higher order convolutional perfectly matched layer (CPML) method is put forward and also applied to cut off the ﬁnite-difference time-domain (FDTD) computational domain full of the unmagnetized plasma. A Drude model can be used to represent the unmagnetized plasma, and the plasma can be solved by using the trapezoidal recursive convolution (TRC) method. In order to verify the validity of the presented method, a numerical example in three-dimensional computational domain is provided. The numerical example results show that the proposed formulations have better absorbing performance than the first-order CPML in terms of attenuating low-frequency and evanescent waves. Besides, by using the proposed method, computational time and memory can be reduced compared to the second order PML implemented by using the auxiliary differential equation (ADE) method.
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