de Paula Rômulo A, Bustamante Yesica R R, Aldaya Ivan
Appl Opt. 2022 Jan 10;61(2):463-470. doi: 10.1364/AO.444985.
Being a fundamental block for systems that utilize polarization-diversity schemes, such as coherent transceivers, polarization rotators allow the conversion of polarization states. In this work, we present an ultra-compact efficient silicon polarization rotator designed via an inverse design method. By optimizing a topology based on the adjoint method, we designed polarization rotators for several combinations of lengths and widths. Simulation results show that the best optimized device presents a polarization conversion loss of 0.67 dB and cross talk of -18 for a central wavelength of 1550 nm. These results were achieved for a 7 µm long and 1.2 µm width device. Furthermore, the high coupling efficiency and low cross talk were achieved for a bandwidth exceeding 100 nm. The polarization conversion loss and cross talk were maintained below 0.82 dB and -18, respectively, for a band ranging from 1500 nm to 1600 nm.
作为诸如相干收发器等利用偏振分集方案的系统的基本组件，偏振旋转器可实现偏振态的转换。在这项工作中，我们展示了一种通过逆设计方法设计的超紧凑高效硅偏振旋转器。通过基于伴随方法优化拓扑结构，我们针对几种长度和宽度的组合设计了偏振旋转器。仿真结果表明，对于中心波长为1550 nm的情况，最佳优化器件的偏振转换损耗为0.67 dB，串扰为 -18。这些结果是针对长度为7 µm、宽度为1.2 µm的器件获得的。此外，对于超过100 nm的带宽，实现了高耦合效率和低串扰。在1500 nm至1600 nm的波段范围内，偏振转换损耗和串扰分别保持在0.82 dB和 -18以下。
