Magnetic and magneto transport properties of Pr0.7Sr0.3MnO3 synthesized by an improved chemical coprecipitation method
By Umesh Chand, G. D. Varma
In the present work, Pr0.7Sr0.3MnO3 particles were prepared by improved chemical coprecipitation method. Structural properties of as prepared sample were investigated using x-ray diffraction and field emission scanning electron microscopy. The analysis of the structure and surface morphologies shows that the sample is in single-phase with the space group of R ͞3C and grain sizes are distributed between 1.5 to 2.0µm. The composition of Pr0.7Sr0.3MnO3 sample was confirmed by energy-dispersive spectroscopy. FTIR spectrum also demonstrate that PSMO particle have formed at 800OC. The magnetization measurements were done using SQUID magnetometer, which shows a reduction in magnetization with temperature. The paramagnetic-ferromagnetic (PM-FM) transition temperature (TC) was appeared at 203K. Resistivity as a function of temperature was measured by a standard four-probe method by using Keithley instruments without or with magnetic fields (0-1T).It has been found that the low-field MR is enhanced owing to tunneling between the large and small Pr0.7Sr0.3MnO3 grains.
Keywords : Magnetoresistance, electrical transport, grain boundary, perovskite material