基于PML边界的有限差分法及其在光波导泄漏损耗计算中的应用

利用结合完美匹配层(PML)边界的有限差分法计算了光波导的泄漏损耗.通过采用非均匀格点差分格式和反正切坐标变换的方法,有效地减小了计算量并提高了计算精度.分析了PI(polyimide)掩埋型波导和SOI(silicon-on-insulator)脊型波导两种典型结构的泄漏损耗,给出了波导结构尺寸对泄漏损耗的影响,并对有效减小泄漏损耗的方法进行了讨论.

A Finite Difference Method with a PML Boundary Treatment and Its Application to the Calculation of the Leakage Loss of an Optical Waveguide

A finite difference method with a perfectly-matched layer boundary treatment is applied to calculate the leakage loss of an optical waveguide. To reduce the memory consumption and improve the numerical accuracy, an arc tangent transformation for the horizontal coordinate and a non-uniformity grid are used. As examples, leakage losses of a buried polyimide waveguide and a silicon-on-insulator rib waveguide are analyzed. Physical reasons for the leakage loss and methods to reduce the leakage loss are also given.