Urbancova Petra, Chylek Jakub, Hlubina Petr, Pudis Dusan
Department of Physics, Faculty of Electrical Engineering and Information Technology, University of Zilina, Univerzitna 1, 01026 Zilina, Slovakia.
Department of Physics, Technical University Ostrava, 17. listopadu 2172/15, 708 00 Ostrava-Poruba, Czech Republic.
Sensors (Basel). 2020 Nov 27;20(23):6788. doi: 10.3390/s20236788.
In this paper, we present a new type of guided-mode resonance (GMR)-based sensor that utilizes a planar waveguide structure (PWS). We employed a PWS with an asymmetric three-layer waveguide structure consisting of substrate/Au/photoresist. The ellipsometric characterization of the structure layers, the simulated reflectance spectra, and optical field distributions under GMR conditions showed that multiple waveguide modes can be excited in the PWS. These modes can be used for refractive index sensing, and the theoretical analysis of the designed PWS showed a sensitivity to the refractive index up to 6600 nm per refractive index unit (RIU) and a figure of merit (FOM) up to 224 RIU. In response to these promising theoretical results, the PWS was used to measure the relative humidity (RH) of moist air with a sensitivity up to 0.141 nm/%RH and a FOM reaching 3.7 × 10%RH. The results demonstrate that this highly-sensitive and hysteresis-free sensor based on GMR has the potential to be used in a wide range of applications.
在本文中，我们展示了一种新型的基于导模共振（GMR）的传感器，该传感器采用平面波导结构（PWS）。我们使用了一种具有非对称三层波导结构的PWS，该结构由衬底/金/光刻胶组成。对结构层的椭偏表征、模拟反射光谱以及GMR条件下的光场分布表明，在PWS中可以激发多个波导模式。这些模式可用于折射率传感，对所设计的PWS的理论分析表明，其对折射率的灵敏度高达每折射率单位（RIU）6600 nm，品质因数（FOM）高达224 RIU。鉴于这些有前景的理论结果，PWS被用于测量潮湿空气的相对湿度（RH），灵敏度高达0.141 nm/%RH，FOM达到3.7×10%RH。结果表明，这种基于GMR的高灵敏度且无滞后的传感器具有在广泛应用中使用的潜力。
