English

Multiorbital processes rule the Nd$_{1-x}$Sr$_x$NiO$_2$ normal state

Strongly Correlated Electrons 2020-10-06 v3 Materials Science Superconductivity

Abstract

The predominant Ni-multiorbital nature of infinite-layer neodynium nickelate at stoichiometry and with doping is revealed. We investigate the correlated electronic structure of NdNiO2_2 at lower temperatures and show that first-principles many-body theory may account for Kondo(-lattice) features. Yet those are not only based on localized Ni-dx2y2d_{x^2-y^2} and a Nd-dominated self-doping band, but heavily builds on the participation of Ni-dz2d_{z^2} in a Hund-assisted manner. In a tailored three-orbital study, the half-filled regime of the former inplane Ni orbital remains surprisingly robust even for substantial hole doping δ\delta. Reconstructions of the interacting Fermi surface designate the superconducting region within the experimental phase diagram. They furthermore provide clues to recent Hall measurements as well as to the astounding weakly-insulating behavior at larger experimental δ\delta. Finally, a strong asymmetry between electron and hole doping, with a revival of Ni single-orbital features in the former case, is predicted. Superconductivity in Nd1x_{1-x}Srx_xNiO2_2 is unlike the one in cuprates of distinct multiorbital kind, building up on nearly localized Ni-dx2y2d_{x^2-y^2} and itinerant Ni-dz2d_{z^2}.

Keywords

Cite

@article{arxiv.2005.01166,
  title  = {Multiorbital processes rule the Nd$_{1-x}$Sr$_x$NiO$_2$ normal state},
  author = {Frank Lechermann},
  journal= {arXiv preprint arXiv:2005.01166},
  year   = {2020}
}

Comments

14 pages, 14 figures, 2 tables

R2 v1 2026-06-23T15:16:39.383Z