We report theoretical predictions on the pairing symmetry of the newly discovered superconducting nickelate Nd1−xSrxNiO2 based on the renormalized mean-field theory for a generalized model Hamiltonian proposed in [Phys. Rev. B \textbf{101}, 020501(R)]. For practical values of the key parameters, we find a transition between a gapped (d+is)-wave pairing state in the small doping region to a gapless d-wave pairing state in the large doping region, accompanied by an abrupt Fermi surface change at the critical doping. Our overall phase diagram also shows the possibility of a (d+is)- to s-wave transition if the electron hybridization is relatively small. In either case, the low-doping (d+is)-wave state is a gapped superconducting state with broken time-reversal symmetry. Our results are in qualitative agreement with recent experimental observations and predict several key features to be examined in future measurements.
@article{arxiv.2006.15928,
title = {Distinct pairing symmetries of superconductivity in infinite-layer nickelates},
author = {Zhan Wang and Guang-Ming Zhang and Yi-feng Yang and Fu-Chun Zhang},
journal= {arXiv preprint arXiv:2006.15928},
year = {2021}
}