A method was presented for the determination of the concentration of Mn ions in non-equivalent interstitial positions in the lattice of (Ga,Mn)As. The Mn ions occupy substitutional and/or interstitial positions in the GaAs lattice and the dependence of the structure factor on their concentration differs for various diffractions and for different positions in the lattice. Several diffractions including weak diffractions were measured, which were very sensitive to the Mn content. All measured diffraction curves were simultaneously fitted to a theoretical model and the densities of Mn ions, in particular interstitial positions, were obtained. The method reported here permitted the determination of the amount of interstitial Mn which, according to current understanding, affected the ferromagnetic properties including the Curie temperature in (Ga,Mn)As.

Study of Mn Interstitials in (Ga,Mn)As using High-Resolution X-Ray Diffraction. L.Horák, Z.Šobáň, V.Holý: Journal of Physics - Condensed Matter, 2010, 22[29], 296009