Strain and correlation of self-organized Ge1-xMnx nanocolumns embedded in Ge (001)

We report on the structural properties of Ge_1-xMn_x layers grown by molecular-beam epitaxy. In these layers, nanocolumns with a high Mn content are embedded in an almost-pure Ge matrix. We have used grazing-incidence x-ray scattering, atomic force and transmission electron microscopy to study the structural properties of the columns. We demonstrate how the elastic deformation of the matrix (as calculated using atomistic simulations) around the columns, as well as the average intercolumn distance can account for the shape of the diffusion around Bragg peaks.