RESUMO
We investigate the detailed analysis of the magnetic properties in a series of Pr1-xSmxFeO3single crystals fromx= 0 to 1 with an interval of 0.1. Doping controlled spin reorientation transition temperatureTSRΓ4(Gx,Ay,Fz) to Γ2(Fx,Cy,Gz) covers a wide temperature range including room temperature. A 'butterfly'-shape type-I spin switching with 180° magnetization reversal occurs below and above the magnetization compensation points inx= 0.4 to 0.8 compounds. Interestingly, in Pr0.6Sm0.4FeO3single crystal, we find an inadequate spin reorientation transition accompanied by uncompleted type-I spin switching in the temperature region from 138 to 174 K. Furthermore, a type-II spin switching appears at 23 K, as evidenced from the magnetization curve in field-cooled-cooling (FCC) mode initially bifurcate from zero-field-cooled (ZFC) magnetization curve at 40 K and finally drops back to coincide the ZFC magnetization value at 23 K. Our current research reveals a strong and complex competition between Pr3+-Fe3+and Sm3+-Fe3+exchange interactions and more importantly renders a window to design spintronic device materials for future potential applications.
RESUMO
We report the physical properties of Eu-doped bulk TmFeO3 through X-ray diffraction, magnetic susceptibility (χ), Raman scattering and X-ray absorption spectroscopy (XAS) study, which shows a similar orthorhombic structure with the Pbnm space group as TmFeO3. Magnetic measurement on Eu-doped TmFeO3 provides evidence for spin reorientations of Fe3+. Further, the Raman spectra of Eu3+ doped TmFeO3 show significant changes in Raman modes as a function of temperature, which are evidence for strong spin-lattice interaction. From the XAS spectra, the L-edge of Fe provides information on the valence state of Fe, whereas the K-edge of oxygen shows that the compound has a strong influence on the hybridization of the O(2p) state with the 3d states of Fe.
RESUMO
The spin switching and exchange bias effect were investigated in the rare earth orthoferrite SmFeO3 composed of two antiferromagnetically coupled sublattices Sm3+ and Fe3+ with canted ferromagnetic moments and a temperature induced spin switching in single crystal SmFeO3 was observed. The spin switching temperature was found to be modulated by exerting different magnetic fields below the compensation temperature ([Formula: see text]). This effect could be explained as the changes of energy barrier related to the magnetization direction under different magnetic fields. In the meantime, the coercivity displayed strong dependence on the maximum applied magnetic fields in the hysteresis measurement. In addition, spontaneous exchange bias effect (EB) was observed with the largest EB field value of 1.2 T, and the EB field changed its sign across the compensation point. Our results indicate that the magnetic properties of SmFeO3 can be strongly affected and controlled by the temperature or the applied magnetic field during the measurement process, and it might lead to novel applications in magneto-optics, ultrafast switching, and magnetic sensing devices.