Examples of single-crystal epitaxial thin films of a high entropy perovskite oxide are synthesized. Pulsed laser deposition is used to grow the configurationally disordered ABO 3 perovskite Ba(Zr 0.2 Sn 0.2 Ti 0.2 Hf 0.2 Nb 0.2)O 3 epitaxially on SrTiO 3 and MgO substrates. X-ray diffraction and scanning transmission electron microscopy demonstrate that the films are single phase with excellent crystallinity and atomically abrupt interfaces to the underlying substrates. Atomically resolved electron-energy-loss spectroscopy mapping shows a uniform and random distribution of all B-site cations. The ability to stabilize perovskites with this level of configurational disorder offers new possibilities for designing materials from a much broader combinatorial cation pallet while providing a fresh avenue for fundamental studies in strongly correlated quantum materials where local disorder can play a critical role in determining macroscopic properties.
Sharma, Y., Musico, B. L., Gao, X., Hua, C., May, A. F., Herklotz, A., … Ward, T. Z. (2018). Single-crystal high entropy perovskite oxide epitaxial films. Physical Review Materials, 2(6). https://doi.org/10.1103/PhysRevMaterials.2.060404