The effect of Dy–Fe co-doping on the structural and magnetic properties of h-YMnO3

The polycrystalline samples of YMn1−xFexO3 (YMFO) and co-doped Y1−yDyyMn0.8Fe0.2O3 (YDMFO) with x ranging from 0 to 0.7 and y from 0 to 0.2 are synthesized by solid state reaction method and comparatively investigated. Structural analysis by X-Ray diffraction and Raman scattering shows that sample crystallizes in a pure hexagonal P63cm phase for YMFO with x ≤ 0.2 and all the co-doped compounds. The tilting angle α of MnO5 bipyramids decreases, while the Mn–OT bond lengths are extended with increasing Fe3+ concentration. These parameters are almost not changed in co-doped samples. The structural results indicate that the distortion of MnO5 is weakened by Fe3+ substitution at Mn3+ site, while those are not altered in YDMFO. Magnetic measurements indicate that the antiferromagnetic interaction is suppressed by Fe3+ doping, which is ascribed to the weakened distortion of MnO5 bipyramids. Weak ferromagnetic ordering is found in Dy–Fe co-doped YMnO3 samples at low temperature, which is resulted from the Dy3+−Fe3+/Mn3+ exchange interaction.