发表机构
The University of Queensland（昆士兰大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出基于部分欧拉弯的几何框架，设计绝缘体上硅平台上的宽带横向模式定向耦合器，实现模式复用与分束，模拟带宽达101-134纳米，实验验证了高转换效率与低串扰。
AI 中文摘要
超越基模的横向模式正越来越多地被探索，以在模分复用和高维量子信息处理中增加信息容量。在宽带宽内以任意比例组合和分离这些模式的能力是这些应用的核心。受多模波导中部分欧拉弯较低弯曲损耗和较低模间串扰的启发，我们开发了一种基于部分欧拉弯的几何框架，用于在绝缘体上硅平台上实现前两个横向电模式之间的宽带功率耦合。我们的方法结合了本征模展开和时域有限差分方法。我们的设计包括一个模式（解）复用器，以及不平衡耦合器（2/3和1/3分束器）。我们的定向耦合器的模拟1-dB带宽范围从101纳米到134纳米。性能最佳的制造模式（解）复用器在1550纳米处测得的1-dB带宽为90纳米，转换效率为94.0%，串扰低于-18分贝。我们的结果验证了部分欧拉弯在宽带横向模式定向耦合器中的应用，并为其设计提供了一个通用框架。
英文摘要
Transverse modes beyond the fundamental mode are increasingly being explored to increase information capacity in both mode-division multiplexing and high-dimensional quantum information processing. The ability to combine and separate these modes at arbitrary ratios over a broad bandwidth is central to these applications. Motivated by the lower bending loss and intermodal crosstalk of partial Euler bends in multimode waveguides, we develop a geometric framework based on partial Euler bends for broadband power coupling between the first two transverse electric modes on a silicon-on-insulator platform. Our methodology uses a hybrid of eigenmode expansion and finite-difference time-domain methods. Our designs feature a mode (de)multiplexer, as well as unbalanced couplers (2/3 and 1/3 splitters). The simulated 1-dB bandwidths of our directional couplers range from $101$ nm to $134$ nm. The best-performing fabricated mode (de)multiplexer has a measured 1-dB bandwidth of $90$ nm, a conversion efficiency of $94.0\%$ and crosstalk below $-18$ dB at $1550$ nm. Our results validate the use of partial Euler bends for broadband transverse mode directional couplers and provide a general framework for their design.
