Synthesis, characterization, and single-crystal growth of a high-entropy rare-earth pyrochlore oxide

The synthesis and single-crystal growth of a rare-earth high-entropy oxide (Yb0.2Tb0.2Gd0.2Dy0.2Er0.2)₂Ti₂O₇ in the cubic pyrochlore phase Fd3̄m are achieved by solid-state reaction and optical floating-zone growth techniques. X-ray diffraction and a structure refinement analysis confirm a single-phase pyrochlore structure and lattice parameter of a=10.1152(3)0.16em0ex. Additional characterization techniques, including scanning transmission electron microscopy and nanoscale electron-energy loss spectroscopy mapping, support a single-phase pyrochlore structure with a homogeneous mixture down to {~}2.3 nm. Magnetization measurements on a single crystal reveal antiferromagnetic correlations with a spin-glass ground state. These results show that it is possible to grow large single crystals of a high entropy pyrochlore oxide, expanding the avenues for future high-entropy oxide research.