Anisotropy of the local atomic structure in Fe-(5–6 at. %) Si single crystals as the cause of formation and stability of induced magnetic anisotropy

Fe1 − xSix (x = 0.05–0.06) single crystals were prepared and subjected to various heat treatments for structural studies. X-ray diffuse scattering measurements detected an anisotropy of regions with local B2-type atomic ordering in samples with induced magnetic anisotropy. It was shown that the average size of ordered clusters as measured along an applied dc magnetic field during heat treatment is slightly larger than that in a transverse direction and reaches 10 Å. Such anisotropy of B2-type regions is not observed in magnetically isotropic samples obtained by rapid quenching or by annealing and cooling in a rotating field (or in the absence of an external field). A comparative analysis of the atomic structure, domain structure, and hysteresis loop shape in samples subjected to various treatments demonstrated a correlation between the short-range order and magnetic properties.