Structural, Magnetic, and Electrical Transport Properties of Nanocrystalline SrCo0.5Mn0.5O&lt;inline-formula&gt; &lt;tex-math notation="LaTeX"&gt;$_{3-\delta}$ &lt;/tex-math&gt; &lt;/inline-formula&gt;

Amit Kumar,Rabindra Nath Mahato,Meenakshi Meenakshi

doi:10.1109/tmag.2018.2821103

Abstract

We report the structural, magnetic, and electrical transport response of nanocrystalline SrCo 0.5 Mn 0.5 O 3-δ compound synthesized by the sol-gel method. X-ray diffraction pattern shows that the sample crystallizes in the hexagonal crystal structure with cubic stacking at room temperature. The compound retains its structural symmetry down to 20 K. The transmission electron microscopy image confirms the surface morphology of the nanocrystalline sample, and the average particle size was found to be ~90 nm. Temperature dependence magnetization data show bifurcation in the zero field cooled (ZFC) and field cooled (FC) magnetization measured under the applied magnetic field of 500 Oe with onset irreversible temperature Tirr ~ 242 K. At low temperature, the small peak has been observed in ZFC curve, suggesting the spin blocking below TB ~ 35 K. The peak has disappeared on the application of higher magnetic field, and the magnitude of bifurcation has also been reduced. The electrical transport data reveal semiconducting such as behavior and follow Mott's variable range hopping (VRH) conduction mechanism in the temperature range 260-300 K. The density of states in the vicinity of Fermi energy is found to be N(EF) ~ 5.702 χ 1018 eV -1 · cm -3 using the VRH fit. The density of state value is in good agreement with the other reported semiconducting oxides. It shows maximum positive magnetoresistance of ~7% at 200 K for the magnetic field change of 3 T.

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