Effect of average A-site cation radius on complex permeability of perovskite manganite La0.65Nd0.05(Sr, Ba)0.3MnO3

A series of polycrystalline perovskite samples La0.65Nd0.05(Sr, Ba)0.3MnO3 were prepared by a sol–gel technique. Their permeabilities have been measured at different fields and temperatures. A pronounced dispersion of the relaxation was observed near the Curie temperature TC, which was obtained from the permeability vs. temperature curves. The effects of the average A-site cation radius 〈rA〉 and the A-site cation disorder parameter σ2(rA) on the permeability were investigated. With increasing 〈rA〉 and σ2(rA), the permeability of La0.65Nd0.05(Sr, Ba)0.3MnO3 increases linearly.