Takagi-Taupin description of x-ray dynamical diffraction from diffractive optics with large numerical aperture

Extension of the time-dependent dynamical diffraction theory to 'optical phonon'-type distortions: application to diffraction from coherent acoustic and optical phonons.

An extension of the time-dependent Takagi-Taupin theory to 'optical phonon'-type distortions is presented. By splitting the susceptibility into the contributions from each atom in a unit cell, modifications to the structure factor as well as lattice parameter are taken into account. The result is a compact, surprisingly simple, equation with a strong formal similarity to the classical Takagi-Ta...

A new approach to the solution of the Takagi± Taupin equations for X-ray optics: application to a thermally deformed crystal monochromator

A new computational approach to the Takagi±Taupin equations for the analysis of X-ray optics is presented and applied to heat-loaded synchrotron monochromators. The new numerical approach is based on the assumption that the incoming wave is completely incoherent (incoherent point source). The simulation avoids any kind of simpli®cation: it takes into account the thermal deformation of the cryst...

X-Ray N-Beam Takagi-Taupin Dynamical Theory and N-Beam Pinhole Topographs Experimentally Obtained and Computer-Simulated

Optimized staircase profiles for diffractive optical devices made from absorbing materials.

We report on the optimization of staircase grating profiles for the case of absorbing grating materials. Using a simple numerical algorithm, we determined the grating parameters, maximizing the first-order diffraction efficiency for different numbers of staircase steps. The results show that there is a significant difference between the staircase profiles for nonnegligible and negligible absorp...

Crystal optics as guard apertures for coherent x-ray diffraction imaging.

A crucial issue in coherent x-ray diffraction imaging experiments is how to increase the signal-to-noise ratio when measuring relatively weak diffraction intensities from a nonperiodic object. A novel crystal guard aperture is described that makes use of a pair of multiple-bounce crystal optics to eliminate unwanted parasitic scattering background. This background is often produced by upstream ...