Matsuda Toyonori, Tsunoda Isao, Koba Shinichiro, Oshiro Yu, Odagawa Hiroyuki
Institute of National College of Technology, Kumamoto College, Kumamoto Campus, 2659-2 Suya, Koshi 861-1102, Kumamoto, Japan.
Institute of National College of Technology, Kumamoto College, Yatsushiro Campus, 2627 Hirayamashin-Machi, Yatsushiro 866-8501, Kumamoto, Japan.
Sensors (Basel). 2024 Mar 20;24(6):1990. doi: 10.3390/s24061990.
We have investigated a polarization property of the (specularly) reflected light from an aluminum grating, coated with a palladium (Pd) thin-film on its surface. The polarization property, which is associated with surface plasmon resonance (SPR), and occurs in the Pd thin-film on the aluminum grating in a conical mounting, is observed as a rapid change in the normalized Stokes parameter s3, around the resonance angle, θsp, at which point, SPR occurs. The sensing technique used the rapid change in s3 to allow us to successfully detect a small change in the complex refractive index of the Pd thin-film layer upon exposure to hydrogen gas, with a concentration near the lower explosion level. Experimental results showed that the sensing technique provided a sensitive and stable response when the Pd thin-film layer was exposed to gas mixtures containing hydrogen at concentrations of 1 to 4% (by volume) in nitrogen.
我们研究了表面涂有钯（Pd）薄膜的铝光栅（镜面）反射光的偏振特性。这种与表面等离子体共振（SPR）相关的偏振特性，在锥形装置中铝光栅上的Pd薄膜中出现，表现为归一化斯托克斯参数s3在共振角θsp附近的快速变化，此时发生SPR。该传感技术利用s3的快速变化，使我们能够成功检测到Pd薄膜层在暴露于氢气（浓度接近爆炸下限）时复折射率的微小变化。实验结果表明，当Pd薄膜层暴露于氮气中氢气浓度为1%至4%（体积）的混合气体时，该传感技术提供了灵敏且稳定的响应。
