Electrical, magnetic, and magnetotransport behavior of inhomogeneous Nd1-xCaxMnO3 (0.0 ≤ x ≤ 0.8) manganites

We have systematically investigated the electrical, magnetic and magnetotransport properties of Nd1-xCaxMnO3 (where x = 0.0 to 0.8) manganites. The substitution of Ca at Nd-site changes the Mn3+/Mn4+ ratio, which in turn influences the electrical and magnetic transport behavior. The temperature dependence of AC susceptibility (ACS) measurements confirmed the inhomogeneity in the magnetic phases for all the compounds. Mostly Nd1-xCaxMnO3 behaves as an insulator under zero and higher magnetic fields. Exemption to that, the intermediate compositions, where x = 0.33-0.5, exhibit a magnetic field induced metal-insulator transition. A significant value of magnetoresistance, 100%, along with a hysteretic nature is obtained for the compositions x = 0.3 to x = 0.5, which attribute to the metamagnetic transitions in the materials. The results have also been explained from the ACS measurements, which are corroborated by the earlier reports.