Growth and electrical transport properties of La0.7Sr0.3MnO3 thin films on Sr2IrO4 single crystals

Abstract

We report the physical properties of ${\mathrm{La}}_{0.7}{\mathrm{Sr}}_{0.3}{\mathrm{MnO}}_{3}$ thin films on ${\mathrm{Sr}}_{2}{\mathrm{IrO}}_{4}$ single crystals. The manganite films are deposited using oxide molecular beam epitaxy on flux-grown (001)-oriented iridate crystals. Temperature-dependent magnetotransport and x-ray magnetic circular dichroism measurements reveal the presence of a ferromagnetic metallic ground state in the films, consistent with films grown on ${\mathrm{SrTiO}}_{3}$ and ${\mathrm{La}}_{0.3}{\mathrm{Sr}}_{0.7}{\mathrm{Al}}_{0.65}{\mathrm{Ta}}_{0.35}{\mathrm{O}}_{3}$. A parallel resistance model is used to separate conduction effects within the ${\mathrm{Sr}}_{2}{\mathrm{IrO}}_{4}$ substrate and the ${\mathrm{La}}_{0.7}{\mathrm{Sr}}_{0.3}{\mathrm{MnO}}_{3}$ thin films, revealing that the measured resistance maximum does not correspond to the manganite Curie temperature but results from a convolution of properties of the near-insulating substrate and metallic film. The ability to grow and characterize epitaxial perovskites on ${\mathrm{Sr}}_{2}{\mathrm{IrO}}_{4}$ crystals enables a new route for studying magnetism at oxide interfaces in the presence of strong spin-orbit interactions.