Tin and lead iodide perovskite semiconductors of the composition AMX3, where M is a metal and X is a halide, are leading candidates for high efficiency low cost tandem photovoltaics, in part because they have band gaps that can be tuned over a wide range by compositional substitution. We experimentally identify two competing mechanisms through which the A-site cation influences the band gap of ...

in this paper a new optical channel drop filter (cdf) based on two dimensional (2-d) photonic crystals (phc) with hexagonal shaped structure is proposed and numerically demonstrated by using the finite-difference-time-domain (fdtd) and plane-wave-expansion (pwe) techniques. photonic crystals (phcs) are artificial dielectric nanostructure materials in which a periodic modulation of the material ...

The effect of evaporation rate on structural, morphological and optical properties of electron beam evaporated CdS thin films have been investigated. CdS thin film deposited by electron beam evaporation method in 12nm/min and 60nm/min evaporation rates on glass substrates. X-ray diffraction, scanning electron microscopy, UV-Vis-NIR spectroscopy and Atomic Force Microscopy were used to character...

We have experimentally investigated the effects of release hole size on acoustic transmission through micromachined phononic band gap crystals. The results confirm previous theoretical studies and determine the range of release hole sizes for which the band gap is minimally compromised. The experiments were performed on micro fabricated 2D phononic crystal plates comprised of high acoustic impe...

To investigate the electromagnetic interaction of molecules inside the nanotubes, first, the structure of nanotubes B16N16 was optimized with hybrid density functional theory (B3LYP) using the EPR-II basis set, then Cu, Cu+, Cu++ were located in nanotube and we studied the total energy, band gap energy, electrical potential, changes of band gap energy in terms of total energy and dipole moment ...