Orbital degree of freedom in high entropy oxides

Understanding strongly correlated physics of electronic-driven orbital ordering in transition metal compounds has presented many long-standing questions. Utilizing high-entropy oxides have enabled understanding that disorder can unlock an unusual intermixing of orbital and spin in the rare-earth vanadate, $R$VO${}_{3}$, which shows that the average and variance of ionic radius determine and control unusual properties of the spin and orbital order. The ability to systematically control variance of the local structure in high-quality crystals which hold constant charge and spin is crucial for a deeper understanding and exploring unanswered decades-old question regarding the physics of the Kugel-Khomskii compounds.