Effective model and pairing tendency in the bilayer Ni-based superconductor La 3 Ni 2 O 7

Since the discovery of cuprates, the origin of high-${T}_{c}$ superconductivity has been an outstanding puzzle. Recently, high-${T}_{c}$ superconductivity was observed in a bilayer nickelate ${\mathrm{La}}_{3}{\mathrm{Ni}}_{2}{\mathrm{O}}_{7}$ under pressure, whose structure hosts the apical oxygen between two layers, distinct from multilayer cuprates. Motivated by this discovery, we investigate its electronic structure using first-principles calculations and superconducting instabilities from both weak-coupling and strong-coupling perspective. Based on the first-principles band structures, we construct a bilayer two-orbital model on a square lattice, consisting of ${d}_{{x}^{2}\ensuremath{-}{y}^{2}}$ and…

• MO
  Ministry of Science and Technology

  Award: 2022YFA1403901
• NN
  National Natural Science Foundation of China

  Awards: 12447103, 12322405, 11920101005, 12494594, 12104450, 12047503, 11888101
• NK
  National Key Research and Development Program of China

  Award: 2023YFA1407300