Lattice and continuum theories of Huang scattering

Abstract

The predicted x-ray and neutron scattering by random semiconductor alloys A 1−x B x C with the zinc-blende structure has been analysed using direct simulation of the scattering from the atoms in the lattice, and also using a continuum theory. This initial work focuses on the special case of the single-impurity limit (small concentration x) where the elastic properties of both of the pure crystals (x = 0 and x = 1) are isotropic and the same. The influence of different atomic scattering amplitudes on the intensity has also been analysed. Distortions occur in the crystal caused by the size mismatch of the impurity atoms, which results in diffuse scattering of which the most important component is the Huang scattering around the Bragg peaks. The Huang scattering has the shape of a double drop and we obtain surprisingly good agreement between the continuum and lattice approaches. This is because long-wavelength concentration waves make the dominant contribution to the divergent Huang scattering, with the remainder of the diffuse scattering being very weak. We have also analysed the influence of elastic anisotropy on the diffuse scattering.

Local structure ofInxGa1−xAssemiconductor alloys by high-energy synchrotron

“…This is the Huang scattering which is peaked close to Bragg-peak positions and has already been worked out in detail. 46 In addition to this, clear streaks are apparent running perpendicular to the [110] direction. The diffuse scattering calculations on (hkl) planes where l = 0, integer ( Fig.…”

Characterization of the microstructure in random and textured polycrystals and single crystals by diffraction line profile analysis

“…In correlation with the reciprocity between the crystal space and reciprocal space the short range distortions produce scattering at long distances from the Bragg reflections. This type of diffraction is known as Huang scattering [5,[23][24][25]. The measurement and determination of Huang scattering is not easy because it appears together with the background scattering [26].…”

Atomic intermixing and interface roughness in short-period InAs/GaSb superlattices for infrared photodetectors

“…In this paper, we concentrate on elastic Bragg scattering neglecting the contribution of Huang scattering from point defects (intermixed atoms), which, in principle, can provide additional information on defect concentrations and defect-induced deformation fields. 21 In our case, the coherent scattering amplitude from the repeating superlattice block is the sum of the scattering amplitudes from each monolayer composing a superlattice period. We start from the GaSb top layer, which is composed of n 0 MLs, and is free of atomic intermixing.…”