Spin reorientation in Dy-based high-entropy oxide perovskite thin films

We present a study on the structural and magnetic properties of thin films of the high entropy perovskite $\mathrm{Dy}\left({\mathrm{Fe}}_{0.2}{\mathrm{Mn}}_{0.2}{\mathrm{Co}}_{0.2}{\mathrm{Cr}}_{0.2}{\mathrm{Ni}}_{0.2}\right)O_3$ (Dy5BO). An element-sensitive investigation was performed using synchrotron-based x-ray absorption spectroscopy, employing x-ray magnetic circular and linear dichroism. The results reveal that the moments residing on the $3d$ transition metal ions and the rare-earth $\mathrm{Dy}$ ions produce a saturation magnetization one order of magnitude larger than any previously studied high-entropy oxide perovskite. Employing temperature-dependent x-ray magnetic linear dichroism, we see clear features of a spin reorientation at the $\mathrm{Mn}$ and $\mathrm{Fe}$ sites, occurring around 18 K, likely driven by the interaction of the corresponding transition metal ions and $\mathrm{Dy}$.