Many-body Electronic Structure of NdNiO$_2$ and CaCuO$_2$
Abstract
The demonstration of superconductivity in nickelate analogues of high cuprates provides new perspectives on the physics of correlated electron materials. The degree to which the nickelate electronic structure is similar to that of cuprates is an important open question. This paper presents results of a comparative study of the many-body electronic structure and theoretical phase diagram of the isostructural materials CaCuO and NdNiO. Important differences include the proximity of the oxygen bands to the Fermi level, the bandwidth of the transition metal-derived bands, and the presence, in NdNiO, of both Nd-derived states crossing the Fermi level and a van Hove singularity that crosses the Fermi level as the out of plane momentum is varied. The low energy physics of NdNiO is found to be that of a single Ni-derived correlated band, with additional accompanying weakly correlated bands of Nd-derived states that dope the Ni-derived band. The effective correlation strength of the Ni-derived -band crossing the Fermi level in NdNiO is found to be greater than that of the Cu-derived -band in CaCuO, but the predicted magnetic transition temperature of NdNiO is substantially lower than that of CaCuO because of the smaller bandwidth.
Keywords
Cite
@article{arxiv.2001.06441,
title = {Many-body Electronic Structure of NdNiO$_2$ and CaCuO$_2$},
author = {Jonathan Karp and Antia S. Botana and Michael R. Norman and Hyowon Park and Manuel Zingl and Andrew Millis},
journal= {arXiv preprint arXiv:2001.06441},
year = {2020}
}