Electronic and Magnetic Structure of Infinite-layer $\textrm{NdNiO}_2$: Trace of Antiferromagnetic Metal

TL;DR

This study uses first-principles calculations to explore the electronic and magnetic properties of undoped NdNiO2, revealing complex Fermi surfaces, tendencies toward antiferromagnetic order, and the influence of Nd 5d-electrons, shedding light on experimental observations.

Contribution

First-principles analysis of NdNiO2's electronic and magnetic structure, highlighting antiferromagnetic tendencies and the role of Nd 5d-electrons, providing insights into its unconventional properties.

Findings

Paramagnetic phase has complex 3D Fermi pockets.

Ni 3d-electrons tend to form antiferromagnetic order with interactions.

Nd 5d-electrons contribute small Fermi pockets affecting magnetism.

Abstract

The recent discovery of Sr-doped infinite-layer nickelate $\textrm{NdNiO}_2$ [D. Li et al. Nature 572, 624 (2019)] offers an exciting platform for investigating unconventional superconductivity in nickelatebased compounds. In this work, we present a first-principles calculations for the electronic and magnetic properties of undoped parent $\textrm{NdNiO}_2$. Intriguingly, we found that: 1) the paramagnetic phase has complex Fermi pockets with 3D characters near the Fermi level; 2) by including electronelectron interactions, 3d-electrons of Ni tend to form $(\pi, \pi, \pi)$ antiferromagnetic ordering at low temperatures; 3) with moderate interaction strength, 5d-electrons of Nd contribute small Fermi pockets that could weaken the magnetic order akin to the self-doping effect. Our results provide a plausible interpretation for the experimentally observed resistivity minimum and Hall coefficient drop. Moreover, we elucidate that antiferromagnetic ordering in $\textrm{NdNiO}_2$ is relatively weak, arising from the small exchange coupling between 3d-electrons of Niand also hybridization with 5d-electrons of Nd.