An ultracompact and low loss polarization-independent 1 ​× ​2 power splitter based on multimode interference (MMI) is designed and analyzed using Eigenmode expansion (EME) and variational FDTD method on silicon on insulator. The numerical tool shows that the excess loss of the power splitter is 0.04 ​dB for TE and 0.06 ​dB for TM polarization at wavelength 1550 ​nm while the polarization differential loss (PDL) is ​< ​0.07 ​dB over wavelength 1500 ​nm–1600 ​nm. Moreover, the optimized MMI structure has a fabrication tolerance of width ±150 ​nm and a length of ±800 ​nm. In addition, polarization-independent arbitrary power splitter (APS) is designed using cascaded MMI and tapered waveguide as a phase shifter having excess loss ​< ​0.16 ​dB for TE and <0.21 ​dB for TM mode at wavelength 1550 ​nm. The proposed devices have broad applications in optical interconnect and switches for PICs.

利用本征模扩展（EME）和变分FDTD方法在绝缘体上硅上设计并分析了基于多模干扰（MMI）的超紧凑，低损耗，偏振无关的1×2功率分配器。数值工具显示，在波长1550 nm处，TE的功率分配器的额外损耗为0.04 dB，对于TM偏振为0.06 dB，而在波长1500 nm时的偏振微分损耗（PDL）<0.07 dB –1600纳米 此外，优化的MMI结构的制造公差为宽度±150 nm和长度±800 nm。此外，使用级联MMI和锥形波导作为移相器设计了偏振无关的任意功率分配器（APS），在波长1550 nm处，TE的额外损耗<0.16 dB，而TM模式的损耗<0.21 dB。