利用辅助微分时域有限差分法求解了任意色散周期模型的电磁波传播问题。利用共轭复数对形式对任意色散媒质进行参数拟合, 并将任意色散媒质的介电常数表示成公式形式, 在FDTD迭代式中引入辅助微分方程, 推导出了适用于多层任意色散模型的通用递推公式, 分别求解了Debye、Drude与太阳能电池周期结构模型的电磁特性仿真问题。仿真结果表明: 数值计算结果与CST商业软件仿真结果基本吻合, 证明了所构建方法的有效性与普适性。

The electromagnetic wave propagation problem of multilayer arbitrary dispersion periodic model was solved by using auxiliary differential equation-finite-difference time-domain (ADE-FDTD) method. The complex-conjugate pole-residue pairs were utilized to fit the parameters of any dispersive medium, and the model’s dielectric constant was expressed as a formula. Furthermore, the ADE was introduced into the FDTD iteration to deduce a general formula applied on the muti-layer arbitrary dispersion model. In addition, the electromagnetic characteristic simulation of Debye, Drude and solar cell structure were respectively solved. Simulation results show that the numerical calculation results are basically consistent with the CST commercial software simulation results, which proves the validity and universality of our method.