Orbital-selective superconductivity in a two-band model of infinite-layer nickelates

摘要

In the present Rapid Communication, we explore superconductivity in NdNiO_2 and LaNiO_2 employing a first-principles derived low-energy model Hamiltonian, consisting of two orbitals: Ni x~2-y~2, and an axial orbital. The axial orbital is constructed out of Nd/La d, Ni 3z~2-r~2, and Ni s characters. Calculation of the superconducting pairing symmetry and pairing eigenvalue of the spin-fluctuation mediated pairing interaction underlines the crucial role of the interorbital Hubbard interaction in superconductivity, which turns out to be orbital selective. The axial orbital brings in material dependence to the problem, making NdNiO_2 different from LaNiO_2, thereby controlling the interorbital Hubbard interaction-assisted superconductivity.