Electronic properties of nickelate-based heterostructures

Epitaxial heterostructures offer multiple strategies to manipulate the interplay between the different degrees of freedom in transition metal oxides. Interfacial structural and electronic couplings are key to tune the functionalities of these materials and even allow access to novel electronic phases.
Perovskite nickelates are interesting materials displaying a metal to insulator transition, with the insulating state characterized by two inequivalent Ni sites. A particular antiferromagnetic order is also stabilized in this low-temperature bond disproportionated state. Through the growth of NdNiO₃/SmNiO₃ superlattices, it will be shown that the existence of a single or double metal-insulator transition temperature can be controlled as function of the layer periodicity. The structural and electronic mechanisms driving this behaviour will be discussed.
Heterostructures also offer large versatility from a synthesis point of view. For example, a double-perovskite heterostructure such as La₂NiMnO₆ can be reproduced as a (111)_pc-oriented LaNiO₃/LaMnO₃ superlattices when 1 monolayer-thick layers are considered. The magnetic properties of the high Curie-temperature ferromagnetic La₂NiMnO₆ heterostructure, synthesized both through a thin film and a superlattice approach, will also be presented.