Studies of Structural, Electrical, and Magnetic Characteristics of Double Perovskite Ceramic: La2FeMnO6

Herein, detailed studies of structural, electrical, and magnetic characteristics of a double perovskite lanthanum iron manganate (La2FeMnO6) are reported. From the Rietveld analysis of X-ray diffraction data and pattern, the orthorhombic structure of the compound is determined. The least-squares refined lattice parameters of the compound are: a = 5.5370 angstrom, b = 7.7988 angstrom, and c = 5.5069 angstrom. The frequency-temperature dependence of the dielectric parameters is explained by the Maxwell-Wagner model to provide the polarization mechanism. Analysis of temperature dependence of impedance and modulus data of different frequency has shown the contributions of grains and grain boundaries in the electrical characteristics of the material. This analysis also shows the semiconductor characteristics, through a negative temperature coefficient of resistance nature. Based on both impedance and modulus spectroscopy, the dielectric relaxation process is found to be of a non-Debye type. The study of scaling behavior of impedance and modulus data suggests that relaxation phenomena are nearly independent of temperature. Detailed analysis of the frequency dependence of conductivity data of different temperatures using the Jonscher's power law has shown the existence of different types of conduction mechanisms in the material. The nature of the current-voltage (I-V) curves suggests that the material behaves as a semiconductor diode type to be used for the rectifying purpose. The conduction mechanism follows the space charge-limited conduction (SCLC) process which is obtained from leakage current analysis. The study of magnetic hysteresis of the material suggests that the material exhibits soft ferromagnetic ordering.