بررسی اثر اندازه‌ی ذرات بر خواص ساختاری و مغناطیسی منگنایت La0.6 Sr0.4MnO3

In this work, La0.6Sr0.4MnO3 manganite particles with nano and micro scales were prepared by Sol-gel and solid state reaction methods. The results from X-ray diffraction analysis by Fullprof software showed that the samples have been crystallized in the rhombohedral structure with (R-3C) space group. Investigation of magnetic properties showed that this compound belong to soft ferromagnetic materials and Curie temperature of the samples shifted to lower temperatures with particle size reduction. Calculation of the effective magnetic moment using Curie-Weiss model showed the magnetic moment reduction of the samples with particle size decreasing. Using magnetization versus field, magnetic saturation reduction, due to particle size decreasing, was observed. The observed behavior described with Core-shell model and the thickness of magnetic dead layer was estimated.