Electronic structure and magnetism in infinite-layer nickelates <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>R</mml:mi><mml:msub><mml:mi>NiO</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math> (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>R</mml:mi><mml:mo>=</mml:mo><mml:mi>La</mml:mi><mml:mtext>−</mml:mtext><mml:mi>Lu</mml:mi></mml:mrow></mml:math>)
Jesse Kapeghian, Antía S. Botana
Abstract
Using first-principles calculations, we analyze the evolution of the electronic structure and magnetic properties of infinite-layer nickelates $R{\mathrm{NiO}}_{2}$ ($R=\text{rare}\phantom{\rule{4.pt}{0ex}}\text{earth}$) as $R$ changes across the lanthanide series from La to Lu. By correlating these changes with in-plane and out-of-plane lattice parameter reductions, we conclude that the in-plane Ni-O distance is the relevant control parameter in infinite-layer nickelates. An antiferromagnetic ground state is obtained for all $R{\mathrm{NiO}}_{2}$ ($R=\text{La-Lu}$). This antiferromagnetic state remains metallic across the lanthanide series and is defined by a multi-orbital picture with low-energy relevance of a flat Ni-${d}_{{z}^{2}}$ band pinned at the Fermi level, in contrast with cuprates. Other non-cuprate-like properties such as the involvement of $R\text{\ensuremath{-}}d$ bands at the Fermi level and a large charge-transfer energy are robust for all $R{\mathrm{NiO}}_{2}$ materials.