Nanophotonics and Applications (NPA) Lab, Department of Physics, Faculty of Science, Beni -Suef University, Beni-Suef, 62514, Egypt.
Yousef Jameel Science and Technology Research Center, American University in Cairo, New Cairo, Cairo 11835, Egypt.
Sci Rep. 2017 Feb 8;7:41983. doi: 10.1038/srep41983.
Gold/one-dimensional photonic crystal (Au/1D-PC) is fabricated and applied for sensitive sensing of glucose and different chemical molecules of various refractive indices. The Au layer thickness is optimized to produce surface plasmon resonance (SPR) at the right edge of the photonic band gap (PBG). As the Au deposition time increased to 60 sec, the PBG width is increased from 46 to 86 nm in correlation with the behavior of the SPR. The selectivity of the optimized Au/1D-PC sensor is tested upon the increase of the environmental refractive index of the detected molecules. The resonance wavelength and the PBG edges increased linearly and the transmitted intensity increased nonlinearly as the environment refractive index increased. The SPR splits to two modes during the detection of chloroform molecules based on the localized capacitive coupling of Au particles. Also, this structure shows high sensitivity at different glucose concentrations. The PBG and SPR are shifted to longer wavelengths, and PBG width is decreased linearly with a rate of 16.04 Å/(μg/mm) as the glucose concentration increased. The proposed structure merits; operation at room temperature, compact size, and easy fabrication; suggest that the proposed structure can be efficiently used for the biomedical and chemical application.
金/一维光子晶体（Au/1D-PC）被制造并应用于对葡萄糖和各种折射率的不同化学分子的敏感传感。Au 层厚度被优化以在光子带隙（PBG）的右边缘产生表面等离子体共振（SPR）。随着 Au 沉积时间增加到 60 秒，PBG 宽度从 46nm 增加到 86nm，与 SPR 的行为相关。在检测分子的环境折射率增加的情况下，优化后的 Au/1D-PC 传感器的选择性得到了测试。共振波长和 PBG 边缘线性增加，而透射强度随着环境折射率的增加非线性增加。在检测氯仿分子时，SPR 分裂为两个模式，这是基于 Au 颗粒的局部电容耦合。此外，这种结构在不同的葡萄糖浓度下表现出高灵敏度。PBG 和 SPR 移至较长的波长，并且 PBG 宽度随葡萄糖浓度的增加以 16.04Å/（μg/mm）的速率线性减小。所提出的结构具有在室温下工作、紧凑尺寸和易于制造的优点；表明所提出的结构可以有效地用于生物医学和化学应用。
