The structure and magnetic properties in Dy3+ doped SmCrO3 ceramics

The Dy3+ doped SmCrO3 polycrystalline ceramics are prepared by solid state method. The structure and magnetic properties are investigated. All samples show orthorhombic structure with space group Pnma. Three magnetic transitions are detected in Dy3+ doped SmCrO3 samples, which arise from the Cr3+-Cr3+ interactions and the spin reorientation of Cr3+, respectively. Both field cooled (FC) and zero field cooled (ZFC) exchange bias (EB) effects are observed in the prepared Sm1-xDyxCrO3 (x = 0 − 0.5) samples below the spin reorientation temperature (TSR), and the EB field (HEB) increases dramatically below TSR. With the increase of the doping level, the HEB is depressed. Three anomalous variations of magnetic entropy change (ΔSM) derived from the isothermal magnetization are observed, which are consistent with the magnetic transitions. Compared with the ΔSM after ZFC processes, the anomalous variations of ΔSM at ~25 K almost disappear after FC processes due to the enhanced unidirectional anisotropy, and no obvious influence is observed for the other two anomalous variations after FC processes.