this paper describes day-one beamlines of the iranian light source facility and design concept of powder diffraction and spectromicroscopy beamlines as the most priorities of each synchrotron that cover the research requirements in the fields of physics, chemistry, nano-science, etc. for powder diffraction beamline energy range is 6-30 kev, resolution: 10-4, flux: 1012(ph/s/0.1%b.w.) and spot s...

We discuss electron diffraction from two counterpropagating light waves with two different frequencies. We show that, even though these waves do not form a standing wave, electron diffraction similar to the conventional Kapitza-Dirac effect, i.e., scattering on a standing wave, is still possible. The nonlinear response of the electron to the laser fields creates a stationary diffraction grating...

An occulter is a large diffracting screen which may be flown in conjunction with a telescope to image extrasolar planets. The edge is shaped to minimize the diffracted light in a region beyond the occulter, and a telescope may be placed in this dark shadow to view an extrasolar system with the starlight removed. Errors in position, orientation, and shape of the occulter will diffract additional...

This paper deals with a new formulation for the diffraction of a plane wave by a periodic grating. As a simple example, the diffraction of a transverse magnetic wave by a perfectly conductive periodic array of rectangular grooves is discussed. On the basis of a shadow hypothesis such that no diffraction takes place and only the reflection occurs with the reflection coefficient −1 at a low grazi...

Based on the modified Kogelnik diffraction efficiency equation, we study the diffraction intensity spectrum and the total diffraction efficiency of reflection volume holographic gratings in photorefractive media. Taking photorefractive LiNbO3 crystal as an example, the effect of the grating parameters and the pulse width on the diffraction properties is presented under the influence of crystal ...

Dispersions of monodisperse macroionic spherical particles self assemble into bcc or fcc crystalline colloidal arrays (CCA), which efficiently Bragg diffract light in the near-IR, visible, and UV spectral regions, depending on the lattice constant and the crystal structure. We report here the observation of an anomalously intense “secondary diffraction”, which occurs at half the wavelength (λB/...

This is the second part of a series of papers where we develop rigorous decay estimates for breather solutions of an averaged version of the non-linear Schrödinger equation. In this part we study the diffraction managed discrete nonlinear Schrödinger equation, an equation which describes coupled waveguide arrays with periodic diffraction management geometries. We show that, for vanishing averag...

Diffraction is a natural phenomenon, which occurs when waves propagate or encounter an obstacle. Diffraction is also a fundamental aspect of modern optics: all imaging systems are diffraction systems. However, like a coin has two sides, diffraction also leads to some unfavorable effects, such as an increase in the size of a beam during propagation, and a limited minimal beam size after focusing...

Diffraction of multi-level atoms by an evanescent wave reflective diffraction grating is modeled by numerically solving the time-dependent Schrödinger equation. We are able to explain the diffraction observed in experiments with metastable Neon. This is not possible using a two-level atom model. The multi-level model predicts sensitive dependence of diffraction on the laser polarization. For pu...

Diffraction grating is periodic module used in many engineering fields, its geometrical conception gives interesting properties of diffraction and interferences, a uniform and periodic diffraction grating consists of a number of identical apertures that are equally spaced, in this case, the amplitude of intensity distribution in the far field region is generally modulated by diffraction pattern...