Hydrothermal synthesis and magnetic properties of multiferroic RMn0.5Fe0.5O3 (R = Tb, Dy, and Ho)

Pure-phased orthorhombic RMn0.5Fe0.5O3 (R = Tb, Dy, and Ho) were successfully synthesized via the low-temperature hydrothermal technique. The nucleation and crystal growth of RMn0.5Fe0.5O3 (R = Tb, Dy, and Ho) were influenced mainly by medium alkalinity, reaction temperature and time. All the three samples are of orthorhombic structure with +3 valences of Mn and Fe. They present morphologies of spheres that are assembled by smaller tabular crystals. Spin reorientation transitions were observed in RMn0.5Fe0.5O3 (R = Tb, Dy, and Ho), and magnetization reversal was observed in TbFe0.5Mn0.5O3. The spin reorientation temperatures show a linear relation with the magnetic field intensity, and the spin reorientation and magnetization reversal disappear when the applied field is big enough. Antiferromagnetic transition of R3+ was observed in TbFe0.5Mn0.5O3 and DyFe0.5Mn0.5O3 at lower temperatures. All the three samples show the characteristics of spiral magnetic ordering at 2 K and show residual magnetism at both 2 K and 300 K.