Structural, Magneto-Transport Properties of Lead Doped NdMnO3 Ceramics

Abstract

Magnetic and magneto-transport properties of Pb doped NdMnO3 system have been reported. Polymeric precursor method has been used to synthesis of Nd1−xPbxMnO3 (0.24 ≤ x ≤ 0.64) samples. Structural and transport properties have been studied by XRD and standard four probe technique respectively. Lattice parameters have been determined using the data from XRD pattern. All the samples Nd1−xPbxMnO3 (0.24 ≤ x ≤ 0.64) have shown orthorhombic structure with space group Pbnm symmetry. The particles size of these powders has been found in the range of 22 nm to 35 nm. Insulator-metal transition (IMT) observed from resistivity (ρ) vs temperature plot, has been found to shift towards high temperature with x up to x = 0.44. Magnetic susceptibility measurements for all these samples from 77 to 300 K confirms the existence of ferromagnetism below Curie temperature. Phase diagram having the information about composition, magnetic phases and TC has been constructed. The Result of ln (ρ) vs Tn, in paramagnetic region reveal that conduction occurs due to variable range hopping (VRH) of electrons in the band of localized states in the absence of electron–electron interactions for x ≤ 0.44 but for x = 0.54 and 0.64 it corresponds to conduction through VRH with a small gap due to electron correlation.