采用光子晶体禁带法检测溶液浓度的新方法研究

New Method of Solution Concentration Detection Using Photonic Band Gap

摘要: 为了研究液体浓度检测用的光子晶体传感器特性，本文选择二维三角晶格光子晶体材料硅(Si)作为基底，在空气孔内填充不同质量摩尔浓度的待测溶液，计算出了溶液填充的光子晶体在不同偏振模式下的禁带宽度。给出了光子带隙中心所在频率位置的理论依据，应用光子晶体平面波展开法和已有的仿真数据。计算出了带隙中心所在频率位置与待测甲醇–水溶液浓度之间的关系。仿真结果表明，待测甲醇–水溶液的浓度与光子带隙中心频率之间存在正比例线性关系，本文选取溶液浓度检测范围为0.05~0.60 mol/L，并对不同结构产生的带隙位置进行了线性拟合，得到最终的拟合公式，这说明甲醇溶液浓度与带隙中心频率位置存在线性函数关系。

Abstract: In order to investigate the characteristics of the photonic crystal sensor for liquid concentration detection, in this paper, two-dimensional triangular lattice photonic crystal material silicon (Si) is chosen as the base, in which a solution with different mass mole concentrations is filled in the air hole to calculate the band gap of the photonic crystals with different polarization modes. The theoretical foundation of the frequency position center of photonic band gap is given. In addition, the relationship between the frequency position of the band gap center and the concentration of the methanol-water solution to be measured are calculated by using the planar wave expansion method and the existing simulation data. The simulation results imply that there is a positive proportional linear relationship between the concentration of the methanol-water solution and the center frequency of the photonic band gap. In this work, the range of solution concentration is 0.05~0.60 mol/L, and the linear fitting of the band gap position produced by different structures is obtained, and the final fitting formula is found, which indicates that the concentration of methanol solution is linear relationship with the center frequency of the band gap.