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 ${({\mathrm{Yb}}_{0.2}{\mathrm{Tb}}_{0.2}{\mathrm{Gd}}_{0.2}{\mathrm{Dy}}_{0.2}{\mathrm{Er}}_{0.2})}_{2}{\mathrm{Ti}}_{2}{\mathrm{O}}_{7}$ in the cubic pyrochlore phase $Fd\overline{3}m$ 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 $a=10.1152(3)\phantom{\rule{0.16em}{0ex}}\AA{}$. 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 \ensuremath{\sim}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.