Abstract: In this study, using density functional theory and the SIESTA computationalcode, we investigate the electronic and optical properties of the armchair graphenenanoribbons and the armchair boron nitride nanoribbons of width 25 in the presence of atransverse external electric field. We have observed that in the absence of the electricfield, these structures are se...

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 ...

The location and nature of the doped elements strongly affect the structural, electronic and optical properties of TiO₂. To tailor the band structure and modify the photoelectrochemical properties of TiO₂, a pair of dopants is selected. Fe and N atoms are inserted in the TiO₂ network at substitutional and interstitial sites with different relative distances. The main objective behind the differ...

An electro-optic tunable single and multi-channel optical filter based on one-dimensional defective photonic crystal (1DDPC) structure is proposed. A couple of externally tunable defects in arrangement of (AB)5D1(BA)D2(BA)5, where A and B are dielectric materials, D1 and D2 are the tunable defects are used. The defects are composed of the ferroelectric LiNbO3 crystals and two pairs of thin Ag l...

We have studied space-charge-induced optical nonlinearities for asymmetric coupled quantum wells. By the spatial separation of heavy holes and electrons, an electrostatic potential is induced which increases the fundamental bandgap. Calculations, using the Hartree approximation, for oqtimi5ed AlGaAs structures show that a blue-shift of the band gap of 9 meV at a carrier density of 10 * cm can b...

In this study, a novel method called “atmospheric pressure solution evaporation (APSE)” wasdeveloped for growing of Zinc Oxide (ZnO) nanostructures on Al2O3 surface. Zinc acetate dihydrate,Polyvinyl Pyrrolidone, and deionized water were used as precursor, capping, and solvent, respectively.The growth of ZnO nanostructures from evaporated solution was performed at three temperatures of300, 400, ...

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 ...