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A new structure to control the electromagnetic waves has been successfully designed for smart windows applications. The present photonic crystals (PCs) smart window is designed from a unit cell of two different materials such as A (metal) and B (superconductor) of thicknesses that repeated for N periods. The numerical results are investigated based on the characteristic matrix method. It was found that the angle of incidence has a significant effect on the transmission values. At 10o angle of incidence, we found more than 80% of the visible light and a near IR is transmitted whereas at 60o angle of incidence, the photonic band gap (PBG) begins to appear at wavelengths greater than 800 nm and the visible light transmittance remains more than 80%. Also, the dependence of the transmittance values on the periodicity and thickness of the proposed design was investigated. The proposed structure could be of potential use as a smart window in low-temperature applications and space industry. [ABSTRACT FROM AUTHOR]

In the present work, we introduce a study about the reflectance properties of a one-dimensional superconductor photonic crystal in a different manner. Our structure is designed from alternately layers of high-temperature superconducting material (BSCCO) and a conventional superconducting material (Nb) terminated by the dielectric cap layer. The investigated numerical results are essentially based on the basics of the transfer matrix method and the two-fluid model. The numerical results showed the appearance of two sharp peaks, which are referred to Fano and electromagnetic-induced reflectance resonances. Also, we demonstrate the effects of many parameters on the reflectance properties of Fano resonance and the electromagnetic-induced reflectance. The effects of the constituent layer thicknesses, the number of periods, the operating temperature, the angle of incidence, and the refractive index of the dielectric cap layer are all considered. Finally, the effects of hydrostatic pressure on the Fano and EIR resonances are studied and calculated. This structure can play an important role in optical switching devices. [ABSTRACT FROM AUTHOR]

Based on the fundamentals of the characteristic matrix method, we theoretically investigate the optical properties of onedimensional superconductor metamaterial photonic crystals. The photonic crystals are composed of a superconductor layer and two semiconductor metamaterial layers of In0.53Ga0.47As with different doping densities. The numerical results show negative values in permittivity of the metamaterial layer along a broad band of the incident radiation. The negative values show a significant effect on the optical properties of the present structure. Moreover, the optical properties of our design can be controlled by different parameters such as thicknesses of the layers, the operating temperature and the doping density. Our results may be suitable for different applications in the optical community. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the properties of photonic band structures in two-dimensional superconductor photonic crystals (2D-SCPCs) using the frequency dependent plane wave expansion method. We consider two types of 2D-SCPCs, which are composed of superconductor (dielectric) rods embedded into a dielectric (superconductor) background, named type I (type II) SCPCs. We target maximization of the gap-to-mid-gap ratio by varying many parameters, namely, shape of the rods, the operating temperature, the permittivity of the dielectric material, and the threshold frequency of the superconductor. We show that the type II SCPCs have a higher gap-to-mid-gap ratio than the type I SCPCs. In addition, the PBGs can be tuned efficiently by the operating temperature. Moreover, the photonic band structures can be tailored by changing the dielectric constant of the background (rods) in the type I (type II) SCPCs. [ABSTRACT FROM AUTHOR]

We present the transmittance of two types of one-dimensional periodic structures. The first type of structure consists of alternating layers of a dielectric material. The second type of structure consists of alternating layers of a dielectric material and a superconductor whose dielectric properties are described by the two-fluid model. The variance of the intensity and the bandwidth of the transmittance are strongly dependent on the thicknesses, temperature, and frequencies. We have compared the transmittance spectra and present some details about the two types of structure. In the first type, we will make a comparison between the optical properties of the high temperature superconducting photonic crystal (HTScPC) by using the YBaCuO as a superconductor layer with SrTiO as a dielectric layer. The second type consists of the dielectric photonic crystals (DPCs) and AlO or MgO with SrTiO within the ultra-violet region. The comparison obtained according to the difference of the thickness of SrTiO and the variance of the number of periods. The common result is changed in the number of PBGs within the UV range. [ABSTRACT FROM AUTHOR]