  It has been shown that oxide ceramics containing multiple transition and/or
rare-earth elements in equimolar ratios have a strong tendency to crystallize
in simple single phase structures, stabilized by the high configurational
entropy. In analogy to the metallic alloy systems, these oxides are denoted
high entropy oxides (HEOs). The HEO concept allows to access hitherto uncharted
areas in the multi-element phase diagram. Among the already realized structures
there is the highly complex class of rare earth - transition element
perovskites. This fascinating class of materials generated by applying the
innovative concept of high entropy stabilization provides a new and manyfold
research space with promise of discoveries of unprecedented properties and
phenomena. The present study provides a first investigation of the magnetic
properties of selected compounds of this novel class of materials.
Comprehensive studies by DC and AC magnetometry are combined with element
specific spectroscopy in order to understand the interplay between magnetic
exchange and the high degree of chemical disorder in the systems. We observe a
predominant antiferromagnetic behavior in the single phase materials, combined
with a small ferromagnetic contribution possibly stemming from small
ferromagnetic clusters or configurations in the antiferromagnetic matrix. In
the long term perspective it is proposed to screen the properties of this
family of compounds with high throughput methods, including combined
experimental and theoretical approaches.

Materials Science