Employing first-principles density functional theory calculations and Wannierization of the low energy band structure, we analyze the electronic structure of undoped, infinite-layer nickelate compounds, NdNiO2, PrNiO2 and LaNiO2. Our study reveals important role of non-zero f-ness of Nd and Pr atoms, as opposed to f0 occupancy of La. The non-zero f-ness becomes effective in lowering the energy of the rare-earth 5d hybridized axial orbital, thereby enhancing the electron pockets and influencing the Fermi surface topology. The Fermi surface topology of NdNiO2 and PrNiO2 is strikingly similar, while differences are observed for LaNiO2. This difference shows up in computed doping dependent superconducting properties of the three compounds within a weak coupling theory. We find two gap superconductivity for NdNiO2 and PrNiO2, and possibility of a single gap superconductivity for LaNiO2 with the strength of superconductivity suppressed by almost a factor of two, compared to Nd or Pr compound.
@article{arxiv.2010.02527,
title = {Superconductivity in Infinite-layer Nickelates : Role of Non-zero f-ness},
author = {Subhadeep Bandyopadhyay and Priyo Adhikary and Tanmoy Das and Indra Dasgupta and Tanusri Saha-Dasgupta},
journal= {arXiv preprint arXiv:2010.02527},
year = {2021}
}