Evolution of magnetic property of La0.8Sr0.2Mn1−xFexO3 (0.0 ≤ x ≤ 1.0) perovskite oxides

Abstract

La_0.8Sr_0.2Mn_1−xFe_xO₃ (0.0 ≤ x ≤ 1.0) polycrystalline powder samples were synthesized using the sol–gel method. X-ray diffraction (XRD) analyses confirmed that the samples have single phase ABO₃ perovskite crystal structure. Magnetic measurements at 10 K indicated that the magnetization decreased from 3.345 to 0.0075 µ_B/formula as x increased from 0.0 to 0.7, then it increased to 0.010 µ_B/formula at x = 1.0. In these samples, a Fe³⁺ cation is canted anti-ferromagnetic coupling with the adjacent Mn³⁺ cation. In crystalline grains of the powder samples, there are magnetic domains (MDs), while each MD makes spontaneous magnetization along the Weiss’s molecule field H_M direction. It is found that the average canted angle θ, between cation magnetic moments and H_M direction, increases with increasing x; for the samples with x ≤ 0.7, the θ value is lower than 90°; for the samples with x = 0.9 and 1.0, the θ value is higher than 90°.