Magnetic anisotropy in ferrites–spinels with frustrated magnetic structure

Abstract The investigation of magnetic properties of diluted ferrite CuGa x Al x Fe 2−2 x O 4 ( x =0.2–0.7), CuGa x Al 2 x Fe 2−3 x O 4 ( x =0.1–0.5), of ferrites–chromates Cu x Ni 1− x Fe 0.6 Cr 1.4 O 4 ( x =0.0–0.4), CuFe 2− x Cr x O 4 ( x =0.0, 0.2, 0.3, 1.0, 1.4 and 1.6), and of diluted ferrites–chromates Ga x Fe 1− x NiCrO 4 ( x =0.0, 0.2, 0.4, 0.6 and 0.8) is carried out. It is revealed that the effective magnetic anisotropy constant in ferrites with frustrated magnetic structure is less than K eff for the ferrites with usual ferrimagnetic ordering by the order of magnitude. It is shown that the phase magnetic transition from anisotropic magnetic state to isotropic state takes place at temperature T t , which is smaller than Curie temperature T C in ferrites with frustrated magnetic structure.