Substitution and strain effect on the magnetism of high-entropy oxides

High-entropy oxides are materials characterized by the intricate magnetic ground state arising from the presence of multiple transition metals and magnetic atoms. We intend to measure XMCD of single crystal perovskite thin films of Nd(Cr0.2Mn0.2Fe0.2Co0.2Ni0.2)O3 and Nd0.7Ca0.3(Cr0.2Mn0.2Fe0.2Co0.2Ni0.2)O3, grown on LaAlO3 substrates to induce strain. The samples are characterized for the composition and XRD was used to probe the film thickness. Muon spectroscopy was performed at PSI, Switzerland, while previous XMCD were measured at KIT Light Source, Germany. The incorporation of Ca is observed to enhance the magnetic response of Ni and Fe, with a concomitant reduction in the Co signal. To comprehensively characterize the magnetic behavior, XMCD hysteresis will be measured at the transition metal L3 edges. The results will help to understand the complex magnetic ground state of these high-entropy oxide materials.