Magnetic Properties of La0.7Ba0.3Mn1−xAlxO3 (0 ≤ × ≤ 0.15) Perovskites

Abstract

The effects of aluminum substitution on the magnetic properties of perovskite type La0.7Ba0.3Mn1−xAlxO3 (0.05 ≤ × ≤ 0.15) compounds have been studied. The phase purity of the samples has been determined with X-ray powder diffraction. Comparison among various structural parameters has been performed to understand the effect of Al3+ substitution at Mn3+ site. The DC magnetization study includes the thermo-magnetic measurements in zero field cooled (ZFC) mode within the temperature range of 100 to 300 K and the isothermal M-H curve at 100 K. It has been observed that incorporation of Al3+ ion at the Mn3+ site significantly affects the exchange interaction processes and hence results in suppressed magnetic moments. It has been observed that the uniform distribution of Al3+ at Mn3+ sites results in weakening of long-range ferromagnetic (FM) ordering in the parent compound. The inclusion of 10–15% of Al3+ significantly affects the double-exchange (DE)-interactions, thereby promotes a non-magnetic phase along with separated short-range FM clusters. The presence of non-magnetic phase and non-spontaneous magnetization among FM clusters has been observed for samples with 10–15% of aluminum substitution.