Structural, magnetic and magneto-electric properties of Cr doped α-Fe_2O_3

摘要

The Cr doped hematite system (α-Fe_(1.4)Cr_(0.6)O_3) was synthesised using chemical co-precipitation route and annealed at 800°C. The crystal structure of the sample was studied usingSynchrotron X-ray diffraction (SXRD) and Raman spectroscopy. The dc magnetization under zero field cooled (ZFC) and field cooled (FC) modes were recorded in the temperature range 10 K-340 K. The immediate observation was the absence of Morin transition, which represents the completion of spin flipping process from in-plane to out of plane direction in hematite structure. The sample showed superparamagnetic blocking of magnetic nanoparticles below 38 K. The magnetic core-shell spin structure was applied to understand the spin dynamics at measurement temperature scale from 10 K to 300 K. The current-voltage (I-V) characteristics exhibited an abnormal resistive switching and Negative differential resistance (NDR). Magnetic field dependence of I-V and current-time measurements revealed magneto-electric properties in the sample.