Effects on the atomic structure and electronic properties of two-dimensional graphene (G) and h-BN sheets related to the coexistence of dopants and defects are investigated by using density functional theory based methods. Two types of extended line defects are considered for pristine G and h-BN sheets. In these sheets, the presence of individual doping increases the charge transport character....

We are concerned with the computation of electronic and optical properties of quantum dots. Using the Energy SCAN (ESCAN) method with empirical pseudopotentials, we compute interior eigenstates around the band gap which determine their properties. Numerically, this interior Hermitian eigenvalue problem poses several challenges, both with respect to accuracy and efficiency. Using these criteria,...

The influence of arrangement of poly(3-hexylthiophene) (P3HT) chains embedded into poly(methyl methacrylate) (PMMA) matrix on photophysical properties, such as electronic absorption spectrum, band gap, and photoluminescence quantum yield, of the formed P3HT aggregates have been studied. It has been found that variation of P3HT fraction in PMMA matrix from 25 to 2 wt% is accompanied with the inc...

The synthesis of ZnO nanoparticles has attracted immense interest because of their unique properties and potential applications in optoelectronic devices. ZnO as a wide band gap semiconductor with large excitation energy becomes one of the most important functional material with near UV-emission, optical transparency, electric conductivity and piezoelectricity. ZnO nanoparticles were prepared b...

A solvent-free fabrication of TiO₂ and ZnO nanonetworks is demonstrated by using supramolecular nanotemplates with high coating conformity, uniformity, and atomic scale size control. Deposition of TiO₂ and ZnO on three-dimensional nanofibrous network template is accomplished. Ultrafine control over nanotube diameter allows robust and systematic evaluation of the electrochemical properties of Ti...

We are concerned with the computation of electronic and optical properties of quantum dots. Using the Energy SCAN (ESCAN) method with empirical pseudopotentials, we compute interior eigenstates around the band gap which determine their properties. Numerically, this interior Hermitian eigenvalue problem poses several challenges, both with respect to accuracy and efficiency. Using these criteria,...

In this study, we report on investigations of the electronic structure of SrTiO3 annealed at temperature ranging between 550 and 840◦C in an ultrahigh vacuum. Annealing induced oxygen vacancies (Ovac) impart considerable changes in the electronic structure of SrTiO3. Using core-level photoemission spectroscopy, we have studied the chemical potential shift (∆μ) as a function of annealing tempera...

The tuning of structural, optical, and electrical properties of Al-doped ZnO films deposited by atomic layer deposition technique is reported in this work. With the increasing Al doping level, the evolution from (002) to (100) diffraction peaks indicates the change in growth mode of ZnO films. Spectroscopic ellipsometry has been applied to study the thickness, optical constants, and band gap of...

We report time-resolved electroabsorption of a weak probe in a 500 μm thick zinc-oxide crystal in the presence of a strong midinfrared pump in the tunneling limit. We observe a substantial redshift in the absorption edge that scales with the cube root of intensity up to 1 TW/cm(2) (0.38 eV cm(2/3) TW(-1/3)) after which it increases more slowly to 0.4 eV at a maximum applied intensity of 5 TW/cm...

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...