Lanthanum doped multiferroic DyFeO3: Structural and magnetic properties.

Lanthanum doped multiferroic DyFeO3 was synthesized by solid state reaction. X-ray diffraction and refinement show that the lattice parameters of Dy1-xLaxFeO3 increase linearly with the La content. Raman spectroscopy reveals that the short-range force constant in Dy1-xLaxFeO3 is decreased by La3+ ion substitution. The spin reorientation phase transition temperature (TSRPT) is observed to decrease along with the doping level. The antiferromagnetic ordering temperature TN of Fe3+ ions is depressed with increasing doping level. Both decreasing TSRPT and decreasing TN indicate that Fe-Dy and Fe-Fe interactions are weakened by La substitution. It is found that the electron configuration of Fe3+ is high spin state and not affected by the La doping in all the samples above TN. [ABSTRACT FROM AUTHOR]