Local structure of ternary semiconducting random solid solutions: Extended x-ray-absorption fine structure ofCd1−xMnxTe

Abstract

The nearest-neighbor distances around Te atoms in the random semiconducting alloy ${\mathrm{Cd}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{x}\mathrm{Te}$ have been determined by the extended x-ray-absorption fine-structure technique. The distribution of the anion-cation distances is bimodal. A model of the microscopic structure of the zinc-blende-type ${A}_{1\ensuremath{-}x}{B}_{x}C$ ternary alloys based on a random distribution of cations has been developed. The model describes the bimodal distribution of nearest-neighbor distances in terms of distortion of the anion sublattice, using only the lattice constant of the alloy and the bond-stretching constants of each binary component. Within the framework of this model we consider also the problem of the structural stability of ${\mathrm{Cd}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{x}\mathrm{Te}$.