The aim of the present study was to evaluate the properties of linear andnonlinear optics of the Schiff base Salen. Crystal structure of nanoparticles wasdetermined by a Bruker make diffractometer, Cu-K X-rays of wavelength (=1.5406Å). The XRD patterns were recorded in the 2 range of 10–90o with a step width of 0.02s-1. The UV-Vis Spectra recorded on a computerized double - beam Shimadzu 255...

   We have investigated the electronic and optical properties of AlN hexagonal nanosheets under different kinds of strains, using the band structure results obtained through the full potential linearized augmented plane wave method within the density functional theory. The results show that 10% uniaxial strain along the zig-zag direction induces an indirect to direct band-gap transition. Th...

A microscopic model is employed to relate the dielectric tensor to the microstructure of isotropic amorphous or cubic crystalline materials. Electrostriction is characterized by dielectric parameters that describe how the dielectric tensor varies with deformation and the resulting change in the microstructure. These dielectric parameters are obtained for small deformations, and expressed in ter...

The procedures used to obtain general expressions for the components of the effective dielectric tensor for electromagnetic waves in inhomogeneous magnetized plasmas are briefly reviewed, and the relationship between these expressions and their counterparts which can be obtained assuming electrostatic fluctuations is discussed. It is argued that a general formulation formerly available in the l...

The dielectric anisotropy of liquid crystals causes director reorientation in an applied electric field and is thus at the heart of electro-optic applications of these materials. The components of the dielectric tensor are frequency dependent. Until recently, this frequency dependence was not accounted for in a description of director dynamics in an electric field. We theoretically derive the r...

The modern quantum theory of polarization in dielectrics has been formulated only in recent years [1]. This development has opened a new era in the first principles theory of ferroelectricity and pyroelectricity [2]. The new theory has been used successfully to calculate, in a well defined and computationally efficient way, the macroscopic polarization changes induced by perturbations other tha...

This paper considers the low-frequency scattering by a circular dielectric cylinder and modifies the exact polarizability tensor to extend the valid region of the known low-frequency solution. When compared to the traditional formulation, the proposed solution is shown to be valid for cylinders with a higher dielectric constant and larger radius. key words: low frequency scattering, polarizabil...

A q-plate is a stratified medium composed of a uniaxial nematic liquid crystal with an inhomogeneous orientation of the optical axis possessing a topological charge q, which looks promising as a switching device. This work reports an approach to diagonalizing the dielectric tensor in q-plates, giving a detailed study of nontrivial tensor coordinate transformations. The relationship between the ...

Almost 100 years ago, two different expressions were proposed for the energy-momentum tensor of an electromagnetic wave in a dielectric. Minkowski’s tensor predicted an increase in the linear momentum of the wave on entering a dielectric medium, whereas Abraham’s tensor predicted its decrease. Theoretical arguments were advanced in favor of both sides, and experiments proved incapable of distin...

Almost a hundred years ago, two different expressions were proposed for the energy–momentum tensor of an electromagnetic wave in a dielectric. Minkowski’s tensor predicted an increase in the linear momentum of the wave on entering a dielectric medium, whereas Abraham’s tensor predicted its decrease. Theoretical arguments were advanced in favour of both sides, and experiments proved incapable of...