We analyze and explore the potential of using a polymer horizontal slot waveguide as light-analyte interactive region to implement a low-cost and highly sensitive liquid refractive index sensor. Numerical analysis shows that the optimized polymer horizontal slot waveguide is able to realize high waveguide sensitivity. With the optimized horizontal slot waveguide, polymer liquid refractive index sensors based on Mach-Zehnder interferometer (MZI) and microring resonator (MRR) are then investigated numerically, and the results show that the MZI-based sensor can achieve high sensitivity of 17024nm/RIU and low limit of detection (LOD) of 1.76×10⁻⁶ RIU while the MRR-based sensor can achieve the sensitivity of 177nm/RIU and the LOD of 1.69×10⁻⁴ RIU with a very small footprint. Compared with the sensors employing conventional silicon or silicon nitride vertical slot waveguide, the sensors employing polymer horizontal slot waveguide exhibit comparable performances but simpler and lower fabrication costs.

中文翻译：

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基于聚合物水平缝波导的低成本高灵敏度液体折射率传感器

我们分析和探索使用聚合物水平缝隙波导作为光-分析物交互区域来实现低成本和高灵敏度液体折射率传感器的潜力。数值分析表明，优化的聚合物水平缝波导能够实现较高的波导灵敏度。利用优化的水平缝隙波导，对基于Mach-Zehnder干涉仪（MZI）和微环谐振器（MRR）的聚合物液体折射率传感器进行了数值研究，结果表明基于MZI的传感器可以实现17024nm / RIU的高灵敏度最低检测限（LOD）为1.76×10 ^-6 RIU，而基于MRR的传感器可实现177nm / RIU的灵敏度和1.69×10 ^-4的LODRIU占用空间非常小。与采用传统的硅或氮化硅垂直缝隙波导的传感器相比，采用聚合物水平缝隙波导的传感器表现出可比的性能，但制造成本更低且更简单。