Surface octahedral distortions and atomic design of perovskite interfaces.

Atomic engineering of perovskite films and interfaces is significantly improved by in situ optimization of reflection high-energy electron diffraction (RHEED) features resulting from surface BO₆ octahedral rotations seen during molecular-beam epitaxy growth. This approach yields Sr-doped manganite films across the phase diagram with magnetotransport properties that are, for the first time, identical to bulk single crystals. Careful structural analysis of manganite/titanate interfaces shows that cation intermixing and unit cell dilations are eliminated, while BO₆ rotations and Jahn-Teller-type elongations are nearly completely suppressed at the interface.