Epitaxial growth and transport properties of compressively-strained Ba2IrO4 films*

Ba2IrO4 is a sister compound of the widely investigated Sr2IrO4 and has no IrO6 octahedral rotation nor net canted antiferromagnetic moment, thus it acts as a system more similar to the high-T (c) cuprate. In this work, we synthesize the Ba2IrO4 epitaxial films by reactive molecular beam epitaxy and study their crystalline structure and transport properties under biaxial compressive strain. High resolution scanning transmission electron microscopy and x-ray diffraction confirm the high quality of films with partial strain relaxation. Under compressive epitaxial strain, the Ba2IrO4 exhibits the strain-driven enhancement of the conductivity, consistent with the band gap narrowing and the stronger hybridization of Ir-t(2g) and O-2p orbitals predicted in the first-principles calculations.

Automated summary

In this study, Ba2IrO4 epitaxial films were synthesized by reactive molecular beam epitaxy and exhibited enhanced conductivity under biaxial compressive strain, consistent with first-principles calculations predicting band gap narrowing and stronger orbital hybridization. High resolution scanning transmission electron microscopy and X-ray diffraction confirmed the high quality of the films with partial strain relaxation.