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In this research, a one-dimensional photonic crystal with such a novel and simple design is introduced to serve as an efficient reflector for infrared (IR) wavelengths. The construction of the proposed photonic crystal design based on the gyroidal geometry is the mainstay of this research to investigate the total reflectivity through a wide band of IR wavelengths. In this regard, [Air/(A/B)10/substrate] is indeed the configuration of the suggested photonic crystal structure. The layer symbols, A and B represent two layers of silver with a gyroidal configuration in host materials of titanium dioxide and silicon, respectively. Meanwhile, our numerical findings demonstrate the existence of a cutoff feature at a wavelength of 1 μ m of the propagating electromagnetic waves. Moreover, the filling fraction of sliver through layers (A) and (B) provides a substantial role in the tunability of the cutoff frequency and the reflectivity of the structure as well. Then, we have taken into account how the host material's thicknesses and refractive indices will affect the proposed structure's reflectance. In particular, the refractive index of the host material could lead to a significant variation of the permittivities of the considered materials. Finally, we think that the proposed structure may be of a great interest in a variety of physical and engineering applications including the optical reflectors, smart windows and solar cells applications as well. [ABSTRACT FROM AUTHOR]

In the present communication, by means of the frequency-dependent plane wave expansion method, we theoretically demonstrate the photonic band structures of a new type of two-dimensional (2D) annular photonic crystals (PCs) called 2D ternary superconductor PCs created by square and triangular lattices. Our idea is based on the appearance of the interfacial layer through a number of experimental works. We mainly investigate the maximization of the photonic band gap (PBG) using two types of ternary superconductor PCs. Type I in which an interfacial layer of Nb low temperature superconductor (LTSC) is encircled by cylindrical rods and a background material of two different dielectric materials. Type II is composed of cylindrical rods of Nb enclosed with an interfacial layer and a background material of the same dielectric materials used in type I. With the calculated photonic band structures, it can be found that the PBG can be significantly enlarged using the ternary structures more than the conventional (binary) structures. In addition, the different distributions of the constituent materials of the ternary structures have a distinct effect on the width of the PBGs. [ABSTRACT FROM AUTHOR]

In this paper, we investigate theoretically the transmission properties of one-dimensional quasi-periodic photonic crystals that containing nanocomposite material in the IR wavelength regions. Our structure is particularly designed using the Fibonacci role. Here, the nanocomposite material is composed of nanoparticles of Ag that are randomly immersed in a host dielectric material of SiO2. Numerical results are mainly investigated based on the well-known characteristic matrix method. The numerical results show the appearance of many photonic bandgaps due to the multiple periodicities of our structure. Furthermore, the effects of the parameters of the nanocomposite such as the volume fraction, the refractive index of the dielectric material and the size of the nanoparticles have distinct effects on the transmittance characteristics of our structure. Wherefore, the proposed structure could be considered the cornerstone for many applications such as multichannel filters and optical switches. [ABSTRACT FROM AUTHOR]

In the present work, we discuss the transmittance properties of one-dimensional (1D) superconductor nanocomposite photonic crystals (PCs) in THz frequency regions. Our modeling is essentially based on the two-fluid model, Maxwell-Garnett model and the characteristic matrix method. The numerical results investigate the appearance of the so-called cutoff frequency. We have obtained the significant effect of some parameters such as the volume fraction, the permittivity of the host material, the size of the nanoparticles and the permittivity of the superconductor material on the properties of the cutoff frequency. The present results may be useful in the optical communications and photonic applications to act as tunable antenna in THz, reflectors and high-pass filter. [ABSTRACT FROM AUTHOR]

In this paper, we theoretically investigate the transmittance characteristics of one-dimensional defective photonic crystal in microwave radiations based on the fundamentals of the characteristic matrix method. Here, the defect layer is magnetized plasma. The numerical results show the appearance of defect peaks inside the Photonic Band Gap. The external magnetic field has a significant effect on the permittivity of the defect layer. Therefore, the position and intensity of the defect peak are strongly affected by the external magnetic field. Moreover, we have investigated the different parameters on the defect peaks as the plasma density, the thickness of the plasma layer and the angle of incidence. Wherefore, the proposed structure could be the cornerstone for many applications in microwave regions such as narrowband filters. [ABSTRACT FROM AUTHOR]

By employing the characteristics matrix method, we have investigated the transmission properties of one-dimensional dielectric-semiconductor metamaterial photonic crystals (PC) at Terahertz (THz) range theoretically. The numerical results show the appearance of cutoff frequency within THz range. Furthermore, the thicknesses of the constituents materials and the filling factor have a significant effect on the cutoff frequency. The proposed structure may be useful in many applications, particularly in THz frequency regions. [ABSTRACT FROM AUTHOR]

We have obtained the optical properties of one-dimensional defective photonic crystals containing nanocomposite materials of Ag as a defect layer in UV region; the permittivity of nanocomposite materials depends on plasmon frequency of metal nanoparticles. Our analysis is based on the fundamentals of the transfer matrix method. We have investigated the effect of many parameters such as metal thickness, volume fraction, and defected dielectric materials on the intensity of a defect layer. [ABSTRACT FROM AUTHOR]