Khanikar Tulika, Singh Vinod Kumar
Appl Opt. 2020 Jan 1;59(1):171-179. doi: 10.1364/AO.59.000171.
A highly sensitive hollow fiber (HF) sensor based on surface plasmon resonance is proposed and analyzed numerically. The sensor design involves a side polished HF with a nanoscale gold film deposited over the polished surface and an analyte filled core. The hollow portion of the fiber serves simultaneously as an analyte channel and core, when filled with high refractive index liquid. By analyzing the modal characteristics of the sensor using the finite element method, it is found that the wavelength sensitivity of the HF sensor varies from 25,642 nm/RIU (refractive index unit) to 60,000 nm/RIU in the range 1.45 to 1.47 RIU along with highest amplitude sensitivity of ${4231.7},,{{\rm RIU}^{-1}}$4231.7RIU. The minimum measurable alteration by the sensor lies in the order of ${{10}^{-6}},,{\rm RIU}$10RIU. The sensor also exhibits a high value of figure of merit (FOM) up to ${976},,{{\rm RIU}^{-1}}$976RIU representing a very good overall performance. Moreover, due to the feasibility of design, the specific application of the sensor to magnetic field sensing is also demonstrated and achieved maximum sensitivity of 1361 pm/Oe.
提出了一种基于表面等离子体共振的高灵敏度中空光纤（HF）传感器，并进行了数值分析。该传感器设计包括一根侧面抛光的中空光纤，在抛光表面沉积有纳米级金膜，以及一个填充有分析物的纤芯。当填充高折射率液体时，光纤的中空部分同时作为分析物通道和纤芯。通过使用有限元方法分析传感器的模态特性，发现在1.45至1.47 RIU范围内，中空光纤传感器的波长灵敏度在25,6,42 nm/RIU（折射率单位）至60,000 nm/RIU之间变化，最高幅度灵敏度为4231.7 RIU⁻¹。传感器可测量的最小变化量约为10⁻⁶ RIU。该传感器还具有高达976 RIU⁻¹的高品质因数（FOM），代表了非常好的整体性能。此外，由于设计的可行性，还展示了该传感器在磁场传感方面的具体应用，并实现了1361 pm/Oe的最大灵敏度。
