Competing magnetic interactions in Dy1−xSmxFe10Si2 compounds

The spin reorientation temperatures of Dy1−x SmxFe10Si2 compounds with x=0, 0.1, 0.2, 0.3, 0.4, 0.6 and 1.0 were investigated using dc magnetization measurements in the temperature range from 5 to 350 K. The spin reorientation (SR) temperature was observed to drop gradually from 255 to 52 K as Sm content was increased from x=0 to 0.4. No SR temperature was observed for x>0.4. Magnetization measurements using vibrating sample magnetometry (VSM) were carried out from room temperature to 650 K to determine the dependence of the Curie temperature on Sm content. The Curie temperatures shifted to higher values as the Sm content was increased. X-ray powder diffraction studies revealed that the substitution of Sm for Dy leads to an increase in the lattice parameter a and the unit cell volume V while the lattice parameter c remained constant.