Self-regulated growth of [111]-oriented perovskite oxide films using hybrid molecular beam epitaxy

Exotic material properties and topological nontrivial surface states have been theoretically predicted to emerge in [111]-oriented perovskite layers. The realization of such [111]-oriented perovskite superlattices has been found challenging, and even the growth of perovskite oxide films along this crystallographic direction has been proven as a formidable task, attributed to the highly polar character of the perovskite (111) surface. Successful epitaxial growth along this direction has so far been limited to thin film deposition techniques involving a relatively high kinetic energy, specifically pulsed laser deposition and sputtering. Here, we report on the self-regulated growth of [111]-oriented high-quality SrVO3 by hybrid molecular beam epitaxy. The favorable growth kinetics available for the growth of perovskite oxides by hybrid molecular beam epitaxy on non-polar surfaces was also present for the growth of [111]-oriented films, resulting in high-quality SrVO3(111) thin films with residual resistivity ratios exceeding 20. The ability to grow high-quality perovskite oxides along energetically unfavorable crystallographic directions using hybrid molecular beam epitaxy opens up opportunities to study the transport properties of topological nontrivial and correlated electron systems.

Automated summary

Exotic material properties and topological nontrivial surface states are theoretically predicted to emerge in [111]-oriented perovskite layers. However, the growth of perovskite oxide films along this crystallographic direction has been proven to be difficult due to the highly polar character of the perovskite (111) surface. Successful epitaxial growth of high-quality SrVO3(111) thin films was achieved by hybrid molecular beam epitaxy, opening up opportunities for studying transport properties of topological nontrivial and correlated electron systems.