Stability and electronic properties of LaNiO2/SrTiO3 heterostructures

Abstract

Infinite-layer nickelate thin films materialize an intriguing new platform for high-temperature unconventional superconductivity, with LaNiO2/SrTiO3 as reference setup. We discuss the relative stability of the elementary interfaces of this system and determine the corresponding electronic band structure. We find substantial changes compared to the bulk, in particular in relation to the 5d orbital contributions to the low-energy physics which can be totally replaced by purely Ni-3d flat bands. The d9 configuration characteristic of cuprates can thus be supplemented by an extra interfacial ingredient destabilizing the normal non-superconducting state in these heterostructures.