الفهرس 
AbstractOnly 14 pages are availabe for public view
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Abstract
In this master thesis, we present some models for applications of photonic crystal structure in particular defective photonic crystal structures. We try to bend the wonderful characteristics of these special structures to design some photonic optical sensors that can deal with many detected samples and give more information about it. The detected sample is involved within the photonic crystal structure as a defect layer whatever it is. These designs can response to the electromagnetic radiations as the Nano-scale of these structures and the radiation wavelengths are close. The sensitivity of these sensors depends on the output, which expresses on the internal behavior of the analytes towards the electromagnetic radiation.
Firstly, in this work, we demonstrate the sensing principle of simultaneously detect the salinity and temperature of seawater using a 1D-defective photonic crystal structure. We designed a one-dimensional defective mode photonic crystal based on the well-known transfer matrix method (TMM) for detecting the seawater salinity and temperature. Our proposed optical sensor is based on the following concept. Since the concentration of the salinity in the seawater changes the refractive index of the seawater, the sensitivity can be calculated by a peak wavelength shift happening in the output transmission spectrum for its variation of different concentrations of samples. By adjusting the design parameters of our proposed structure such as the thickness of the defect layer, the temperature and the salinity, we investigated the corresponding optical properties response where the resulted transmittance peak can be turned over the considered range.
Second, we suggest theoretically a defective photonic crystal structure for the sensing principle to detect the soil components. The 1D-PC depends on a numerical method that is known as transfer matrix method (TMM). In our study, the TMM describes the interaction between the soil components and the electromagnetic waves near infrared (NIR) region. Some optical properties of the suggested structure are presented by changing amounts of the soil components such as the volumetric moisture, the temperature, the clay content, and bound water in addition to free water. The quantities of these components affect the complex relative permittivity that helps in studying the transmittance spectrum for the soil samples. The performance of our proposed device is determined by calculating the shift happened in the wavelength of resonance peak when the refractive index of the moist soil is variable. Then, we present and explore the optimization of design parameters for the proposed optical soil sensor, which in turn gives a high performance based on estimating the sensitivity in addition to the quality factor values. Moreover, the sensitivity of the proposed optical sensor can reach to 37134 μm/RIU, 41400 μm/RIU, and 43780 μm/RIU with quality factor values of 42400, 75788.4, and 71941 by changing the volumetric moisture, the temperature, and the amount of clay content through our sample, respectively.