Revisiting the role of strain engineering in NdNiO3 thin film from first-principles calculations

Epitaxial strain engineering of the metal-insulator transition temperature (TMIT) in RNiO3 thin film attracts nowadays extensive attention. Various concrete examples have been reported but the precise mechanism behind the monitoring of TMIT remains elusive.1-6 Here, combining first-principles calculations and Landau theory analysis, we provide a general insight into the effect of epitaxial strain on the properties of NdNiO3 thin films and provide a complete and consistent description of the evolution of TMI under different strain conditions as observed in experiments. We clarify how the subtle interplay between substrate controlled oxygen octahedral rotations and pure lattice strain govern TMI through renormalization of the stiffness of the breathing distortion. Our findings not only improve the understanding of epitaxial strain engineering but also establish practical design rules to purposely and precisely tune TMIT.