Enhancement of Magnetoresistance Effect in La0.8-xDyxNa0.2MnO3 (x = 0.00 and 0.10) Monovalent Doped Manganites: Next Generation Spintronic-Based Devices

Abstract

La_0.8-xDyxNa_0.2MnO₃ (x=0.00 and 0.10) samples were prepared by the solid-state reaction method to investigate the effect of Dy substitution at the La-site on magnetoresistive behaviour in monovalent doped manganites. Analysis of X-ray diffraction data using Rietveld refinement analysis shows that the cell volume decreased from 404.24 Å3 to 401.73 Å3 indicating the enhancement of lattice distortion as a result of Dy substitution. The resistivity versus temperature, ρ-T curve shows that the x=0.00 sample exhibits metallic behaviour in the temperature range of 30 K to 300 K. However, the x=0.10 sample exhibit metal-insulator transition, TMIat 220 K. In the presence of 0.8 T of magnetic field, both samples exhibit a reduction in resistivity in the temperature range of 30 K to 300 K which led to magnetoresistance effect. The observed reduction of resistivity indicates an improvement in ferromagnetic interaction between Mn ions, thus conduction process of charge carriers increased. Dy substituted sample exhibit larger magnetoresistance (MR) effect with a value of 48% compared to the x=0.00 sample with a value of 10% at 300 K, indicating a high sensitivity of the sample to the magnetic field and its potential application for spintronic-based devices.