Ab Initio Downfolding Based on the GW Approximation for Infinite-Layer Nickelates

Motoaki Hirayama, Yusuke Nomura, Ryotaro Arita

Research output: Contribution to journalArticlepeer-review

Abstract

We derive an effective three-orbital model for the infinite-layer nickelates based on the band structure obtained by the GW approximation (GWA), where we consider the Ni 3 (Formula presented.) and O 2p orbitals forming the σ-bond. In the GWA, the self-energy correction to the local density approximation (LDA) increases the energy difference between Ni (Formula presented.) and O 2p, which reduces the bandwidth of the antibonding 3 (Formula presented.) orbitals. The isolation of the Ni (Formula presented.) around the Fermi level suppresses the screening effect. As a result, the correlation effect becomes more significant than that in the model constructed by the LDA-based downfolding. Furthermore, the Mott-Hubbard type character is enhanced in the GWA-based effective model, because the charge-transfer energy increases more rapidly compared to the increase in the interaction parameters.

Original languageEnglish
Article number824144
JournalFrontiers in Physics
Volume10
DOIs
Publication statusPublished - 2022 Feb 23
Externally publishedYes

Keywords

  • ab initio downfolding
  • density functional theory
  • GW approximation
  • multi-orbital Hubbard model
  • nickelate superconductivity

ASJC Scopus subject areas

  • Biophysics
  • Materials Science (miscellaneous)
  • Mathematical Physics
  • Physics and Astronomy(all)
  • Physical and Theoretical Chemistry

Fingerprint

Dive into the research topics of 'Ab Initio Downfolding Based on the GW Approximation for Infinite-Layer Nickelates'. Together they form a unique fingerprint.

Cite this