Possible s ± -wave superconductivity in La 3 Ni 2 O 7

For the new high-temperature superconductor La${}_{3}$Ni${}_{2}$O${}_{7}$ under high pressure, the authors analyze its pairing mechanism and pairing symmetry in a bilayer two-orbital Hubbard model. By combining functional renormalization group in weak-to-moderate interaction regime and Gutzwiller approximation for its low-energy effective model projected to atomic one- and two-electron states in the strong-coupling regime, they find robust extended $s$-wave or ${s}_{\ifmmode\pm\else\textpm\fi{}}$-wave pairing as triggered by spin fluctuations.

• NN
  National Natural Science Foundation of China

  Awards: 12274205, 11874205, 12374147
• NK
  National Key Research and Development Program of China

  Award: 2022YFA1403201