الفهرس 
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Abstract
This thesis introduces novel phoxonic and photonic designs for detecting and sensing different organic compounds and biomaterials. Moreover, it utilizes the power of photonic crystals to enhance human masks and air purifiers in air ventilation systems. The transmittance of photonic and phononic structures is calculated using the well-known transfer matrix method in its cartesian and cylindrical geometries.
In chapter 1, a broad introduction of photonic crystals and their applications are announced, followed by a competitive introduction of phononic crystals. Then, the phoxonic crystals and metamaterial are stated with their properties and applications.
In chapter 2, Multilayer periodic structure with a defect layer is introduced as a sensor for a variety of organic compounds. Here, the interaction of both electromagnetic and acoustic radiations is considered with the designed sensor, which could offer flexibility in the detection process. Si and MgO are the basic materials in the design of the proposed sensor. In this context, this sensor is configured as, {Si (Si / MgO) N (liquid) (MgO / Si) N Si}. The optimization procedure is based on the change of the thickness of the defect layer and the periodicity of the structure as well. The theoretical analysis of this structure is mainly based on the investigation of the photonic and acoustic transmittance as the defect layer is filled with Water, Benzene, Di-isopropyl Ether (DIPE), n Heptane, n Hexane, and n Octane. The analysis includes determining their defect peak frequency, full width at half maximum, quality factor, sensitivity, and figure of merit. The calculated photonic sensitivity for n Heptane is 43.8 (THz/RIU) with 154.8(RIU)^(-1) figure of merit, while its acoustic sensitivity equivalent 1.614 (MHz/ms^(-1)) with a figure of merit equals 1.06
(m/s)^(-1) . from the simulation results, the structure shows a promise response for sensing different organic compounds with high sensitivity.
In chapter 3, a new design to measure the permittivity in the GHz range of non-magnetic biomaterials is introduced. The proposed design is tested with a wide range of cell organelles biomaterials such as Cytosol, Nucleus, Nucleolus, Mitochondria, and Lysosome. The newly proposed designed structure has a maximum sensitivity of 0.496 GHz/RIU. Moreover, it can measure permittivities in the range from 1 up to 9. The main component of the designed structure is a defective one-dimensional photonic crystal with a unit cell consisting of metamaterial and silicon. Also, we demonstrate the role of the metamaterial in enhancing our design. We also examine the impact of the defect layer thickness on the proposed structure.
In chapter 4, a new enhancement to Ultraviolet (UV) air purifiers in air ventilation systems were introduced, which deliver higher inactivation UV dose, eliminating the need for neither higher exposure time nor a stronger UV source. The modified transfer matrix method in the cylindrical geometry represents the main tool of our theoretical considerations. The new enhancement utilizes an annular photonic crystal (APC) for reflecting UV radiation with 99%. The numerical simulation shows that the structure is stable over a wide range of operating scales that fit the extensive range of air purifies, working at different scales. Additionally, the possibility of using APC over a wide range of UV sources is investigated.
In chapter 5, a novel enhancement to a human mask that promises to increase the Ultraviolet germicidal irradiation effect on the pathogens was introduced. The proposed design consists of a tube with an annular photonic crystal attached to the mask’s orifice and a UV source in the tube’s center. The reflection of UV radiation from APC enhances the UV dose. Therefore, increasing pathogens’ inactivation level in the incoming air to the mask’s orifice. The structure’s simulation shows great stability with changing the azimuthal number at both TE and TM modes, which offer full utilization of the UV radiation boosting the structure efficiency. Additionally, The simulation shows that our structure could easily adjust to support a wide range of UV sources by altering the unit cell’s layers thicknesses. Moreover, the simulations also studied the periodicity number, which can be adjusted to optimize the intensity of reflectance and fabrication ease. The numerical results in this thesis have been calculated through custom scripts written in m-language and executed using MathWorks MATLAB R2020a.