Prediction of s± -Wave Superconductivity Enhanced by Electronic Doping in Trilayer Nickelates La4Ni3 O10 under Pressure

Motivated by the recently reported signatures of superconductivity in trilayer La4Ni3O10 under pressure, we comprehensively study this system using ab initio and random-phase approximation techniques. Without electronic interactions, the Ni d3z2-r2 orbitals show a bonding-antibonding and nonbonding splitting behavior via the O pz orbitals inducing a "trimer"lattice in La4Ni3O10, analogous to the dimers of La3Ni2O7. The Fermi surface consists of three electron sheets with mixed eg orbitals, and a hole and an electron pocket made up of the d3z2-r2 orbital, suggesting a Ni two-orbital minimum model. In addition, we find that superconducting pairing is induced in the s±-wave channel due to partial nesting between the M=(π,π) centered pockets and portions of the Fermi surface centered at the Γ=(0,0) point. With changing electronic density n, the s± instability remains leading and its pairing strength shows a domelike behavior with a maximum around n=4.2 (∼6.7% electron doping). The superconducting instability disappears at the same electronic density as that in the new 1313 stacking La3Ni2O7, correlated with the vanishing of the hole pocket that arises from the trilayer sublattice, suggesting that the high-Tc superconductivity of La3Ni2O7 does not originate from a trilayer and monolayer structure. Furthermore, we confirm the experimentally proposed spin state in La4Ni3O10 with an in-plane (π, π) order and antiferromagnetic coupling between the top and bottom Ni layers, and spin zero in the middle layer.