Extracting Complex Dielectric Properties From Reflection-Transmission Mode Spectroscopy
Extracting Complex Dielectric Properties From Reflection-Transmission Mode Spectroscopy
复制标题
从反射-透射模式光谱中提取复杂的介电特性
DOI：
10.1109/access.2018.2797698
复制
发表时间：
2018
期刊：
影响因子：
3.9
通讯作者：
S. Lucyszyn
中科院分区：
文献类型：
--
作者：
Jingye Sun;S. Lucyszyn
由于相量项的模糊性，使用反射-透射模式光谱对均匀电介质板的材料表征可能是有问题的。一个全面的分析审查的方法计算归一化功率谱，提取有效的复杂的介电性能的样品，进行。三个通用的功率响应模型（零阶，功率传播，电场传播）推导出这些模型作为一个统一的数学框架，为整个文件。与我们统一的工程方法，电压波传播，传输线，电报员的方程传输线模型，然后独立地导出;前两个给出相同的数学解，而第三个产生相同的数值结果，作为精确的电场传播模型。数学上可追溯的模拟结果从各种模型进行比较和对比，使用任意选择的数据集（窗口玻璃）从1到100太赫兹。我们展示了如何使用时间选通时域光谱提取近似的有效复介电特性，以及使用我们的理论图形技术从一阶反射率和透射率提取精确值。我们的方法，然后采取进一步考虑所有的法布里-珀罗反射的频域和空域光谱。与标量反射-透射模式红外光谱，我们模型的阈值条件之间的解决方案空间，给出了单一的（精确）的解决方案的复杂的折射率和解决方案空间，给出了多个数学解决方案。通过了解阈值条件，就可以采用的样品约束和计量技术而言，可以获得更深入的了解，以确定单个解决方案。最后，我们提出了一个简单的额外的测量/模拟步骤，以解决多解空间内的模糊性。这里，样品厚度是任意的，不需要初始猜测。理论上，本文的结果允许使用更简单和更低成本的标量反射-透射模式光谱精确提取复杂的介电特性。
Material characterization of homogeneous dielectric slabs using reflection–transmission mode spectroscopy can be problematic due to the ambiguity from a phasor term. A comprehensive analytical review of methods for calculating the normalized power spectra, to extract the effective complex dielectric properties of a sample, is undertaken. Three generic power response models (zero-order, power propagation, and electric-field propagation) are derived; these models act as a consolidated mathematical framework for the whole paper. With our unified engineering approach, the voltage-wave propagation, transmission line, and telegrapher’s equation transmission line models are then independently derived; the first two giving the same mathematical solutions, whereas the third generates the same numerical results, as the exact electric-field propagation model. Mathematically traceable simulation results from the various models are compared and contrasted using an arbitrarily chosen data set (window glass) from 1 to 100 THz. We show how to extract the approximate effective complex dielectric properties using time-gated time-domain spectroscopy and also the exact values with our theoretical graphical techniques from the first-order reflectance and transmittance. Our approach is then taken further by considering all the Fabry–Pérot reflections with the frequency- and space-domain spectroscopy. With the scalar reflection–transmission mode infrared spectroscopy, we model the threshold conditions between the solution space that gives the single (exact) solution for the complex refractive index and the solution space that gives multiple mathematical solutions. By knowing threshold conditions, it is possible to gain a much deeper insight, in terms of the sample constraints and metrology techniques that can be adopted, to determine the single solution. Finally, we propose a simple additional measurement/simulation step to resolve the ambiguity within the multiple solution space. Here, sample thickness is arbitrary and no initial guesses are required. In theory, the result from this paper allows for the exact extraction of complex dielectric properties using simpler and lower cost scalar reflection–transmission mode spectroscopy.