Search

The latest developments in communication systems require an economical, light‐weight, compact size, and excellent performance in microstrip patch antennas in order to meet the requirements of the upcoming implementation. The optical, electrical, and physical properties of different materials have an impact on the design of antennas. An innovative composite photonic crystal microstrip patch antenna with outstanding gain has been developed. For composites of fumed silica embedded in RT‐Duroid dielectric material, the effective permittivity is calculated using the Maxwell‐Garnett model. The performance of composite antennas for different volume fractions and various dielectric substrate thicknesses is studied. The resonance frequencies of composites also shift from the X‐band to the C‐band with an increase in volume concentration, which is suitable for wireless communication systems. This investigation provides a perspective on how composite substrates can represent a communication revolution by providing an alternative to substrates that are readily accessible commercially in situations when the material qualities are insufficient. The photonic crystal composite antenna records the highest gain of 13.89 dB with the coverage of C‐band, X‐band, and Ku‐band, whereas the composite antenna reaches the best gain of 10 dB with the coverage of C‐band and X‐band. [ABSTRACT FROM AUTHOR]

The aim of this work is to minimize reflection losses in order to increase the efficiency of solar cells by using anti‐reflection coatings (ARCs). Despite extensive research on improving solar cell conversion efficiency at normal incidence, development at angle of incidence has received little attention. Thus, the reflectivity of single‐layer ARC (SLARC) MgF2 and ZnSe, double‐layer ARC (DLARC), MgF2/ZnSe on Si, and GaAs substrates at transverse electric (TE) and transverse magnetic (TM) modes of polarization in the visible and near‐IR regions for different angles of incidence is analyzed. The optical and electrical properties of Si and GaAs solar cells are analyzed by using the reflectance spectra of SLARC and DLARC at various angles of incidence for the TM and TE modes of polarization under the solar power spectrum (AM1.5). The achieved results due to the effect of DLARC are compared for Si and GaAs solar cells. From these analyses, it is concluded that MgF2/ZnSe is an appropriate DLARC for the range of wavelengths 400–800 nm at 10°–30° angles of incidence in TM mode for tuning the optical and electrical properties of Si and GaAs substrates for terrestrial applications. [ABSTRACT FROM AUTHOR]

Copper nanoparticles (Cu) anchored lithium niobate (LiNbO3) nanostructures were prepared by a simple hydrothermal technique. The fine and sparse Cu nanoparticles were homogeneously dispersed over the surface of LiNbO3. An effectual anchoring of Cu was evidenced from the acquired reflection planes in diffraction analysis, which clearly indicate the face-centered cubic structure of Cu. The UV-Visible spectrum of LiNbO3 and Cu/LiNbO3 nanocomposites were also studied. When the Cu nanoparticles were doped with LiNbO3/LiTaO3 superlattice system, the change in the dispersion relation was observed theoretically. The characteristics of the polariton dispersion variation with filling factor of Cu nanoparticles concentration were investigated systematically. The importance of the polariton modes in communication sector was analyzed and the occurrence of new modes on the polaritonic gap, where the propagation of the electromagnetic wave is forbidden, were obtained in the system due to the presence of copper nanoparticles. [ABSTRACT FROM AUTHOR]

In this study the effect of theoretically designed SnO2/ZnO double layer anti reflective coating (DLARC) on SnS chalcogenide-based thin-film solar cell is studied. The efficiency of SnS chalcogenide-based thin-film is calculated theoretically and compared with the experimental data available in the literature. The parameters which decide the efficiency such as short circuit current (Jsc), internal and external quantum efficiencies (IQE, EQE) are calculated with and without DLARC using Thelen and Musset numerical method. It is found that values Jsc, IQE and EQE of the SnO2/ZnO DLARC coated on SnS chalcogenide-based thin-film solar cell has increased when compared to bare SnS thin film solar cell as the reflectivity reduction up to 10% in wavelength range of 400–800 nm which is achieved by the DLARC. As a result, SnO2/ZnO DLARC increases the efficiency of SnS chalcogenide-based thin-film solar cells. [ABSTRACT FROM AUTHOR]

The transmission properties of one-dimensional novel photonic crystal having silver-doped novel piezoelectric superlattice and air as the two constituent layers have been investigated by means of transfer matrix method. By changing the appropriate thickness of the layers and filling factor of nanocomposite system, the variation in the photonic band gap can be studied. It is found that the photonic band gap increases with the filling factor of the metal nanocomposite and with the thickness of the layer. These structures possess unique characteristics enabling one to operate as optical waveguides, selective filters, optical switches, integrated piezoelectric microactuators, etc [ABSTRACT FROM AUTHOR]