Electronic transitions in strained SmNiO3 thin films

Nickelates are known for their metal to insulator transition (MIT) and an unusual magnetic ordering, occurring at T = TNéel. Here, we investigate thin films of SmNiO3 subjected to different levels of epitaxial strain. We find that the original bulk behavior (TNéel < TMI) is strongly affected by applying compressive strain to the films. For small compressive strains, a regime where TNéel = TMI is achieved, the paramagnetic insulating phase characteristic of the bulk compound is suppressed and the MIT becomes 1st order. Further increasing the in-plane compression of the SmNiO3 lattice leads to the stabilization of a single metallic paramagnetic phase.