Structure, magnetic and magnetoresistance properties of Pr_(0.67)Sr_(0.33)MnO_3 manganite oxide prepared by ball milling method

摘要

A sample of Pr_(0.67)Sr_(0.33)MnO_3 nanoparticles was synthesized by the ball milling method. X-ray diffraction pattern of the sample showed orthorhombic system with Pnma space group. The average crystallite size of 110 nm was obtained by both Scanning Electron Microscopy and X-ray diffraction. Magnetic measurements showed para-to-ferromagnetic transition with a Curie temperature of T_c=269 K. Electrical investigations showed that all our samples exhibit a semi-conducting behavior above T_c and a metallic-like one at lower temperatures. The sample exhibited a large magnetoresis tance of 30% at room temperature in an applied magnetic field of 2 T. The transport and the magnetic properties were interpreted in terms of the existence of magnetic polarons in the sample.