Pairing Symmetry Crossover from $d$-wave to $s_{\pm }$-wave in a Bilayer Nickelate Driven by Hund's Coupling and Crystal Field Splitting

Abstract

The pairing symmetry of the recently discovered bilayer nickelate superconductor La${}_3$Ni${}_2$O${}_7$ is a subject of intense debate in condensed matter physics, with the two leading theoretical candidates being a sign-reversing $s_{\pm }$-wave and a $d$-wave state. To investigate its ground-state properties in the intermediate coupling regime which is critical for real materials, we construct a two-orbital bilayer Hubbard model and employ the constrained-path quantum Monte Carlo method for large-scale simulations. By systematically calculating ground-state pairing correlation functions across parameter spaces, we map its pairing symmetry phase diagram. We find that an increasing Hund's coupling selectively enhances the interlayer $s_{\pm }$-wave pairing while suppressing the intralayer $d$-wave pairing. Similarly, a larger crystal field splitting drives a transition from $d$-wave- to $s_{\pm }$-wave-dominant states. Further analysis reveals that the strength of the intralayer $d$-wave pairing is strongly correlated with the $(\pi ,\pi )$ antiferromagnetic spin fluctuations, which are in turn effectively suppressed by a large crystal field splitting, thereby weakening the $d$-wave pairing channel. Additionally, the dominant pairing symmetry transition region roughly overlaps with the inversion of orbital occupancy response to Hubbard $U$, suggesting an intrinsic link between pairing competition and orbital physics. Our results indicate that, within the parameter regime relevant to the actual material, the $s_{\pm }$-wave is the most probable pairing symmetry.

9 pages, 6 figures

References in corpus (36)

• Computational complexity and fundamental limitations to fermionic quantum Monte Carlo simulations
• Superconductivity near 80 Kelvin in single crystals of La3Ni2O7 under pressure
• Bilayer two-orbital model of La${}_3$Ni${}_2$O${}_7$ under pressure
• Possible $S_{\pm }$-wave superconductivity in La${}_3$Ni${}_2$O${}_7$
• The s${}^{\pm }$-Wave Pairing and the Destructive Role of Apical-Oxygen Deficiencies in La${}_3$Ni${}_2$O${}_7$ Under Pressure
• Possible high $T_c$ Superconductivity in La${}_3$Ni${}_2$O${}_7$ under High Pressure through Manifestation of a Nearly-Half-Filled Bilayer Hubbard Model
• Electronic correlations and superconducting instability in La${}_3$Ni${}_2$O${}_7$ under high pressure
• Interlayer Coupling Driven High-Temperature Superconductivity in La${}_3$Ni${}_2$O${}_7$ Under Pressure
• Orbital-Dependent Electron Correlation in Double-Layer Nickelate La3Ni2O7
• Bilayer $t$-$J$-$J_{\perp }$ Model and Magnetically Mediated Pairing in the Pressurized Nickelate La${}_3$Ni${}_2$O${}_7$
• Structural phase transition, $s_{\pm }$-wave pairing and magnetic stripe order in the bilayered nickelate superconductor La${}_3$Ni${}_2$O${}_7$ under pressure
• Electronic and magnetic excitations in La${}_3$Ni${}_2$O${}_7$
• Electronic correlations and partial gap in the bilayer nickelate La${}_3$Ni${}_2$O${}_7$
• Flat bands promoted by Hund's rule coupling in the candidate double-layer high-temperature superconductor La${}_3$Ni${}_2$O${}_7$
• Normal and superconducting properties of La${}_3$Ni${}_2$O${}_7$
• Electron correlations and superconductivity in La${}_3$Ni${}_2$O${}_7$ under pressure tuning
• Competing d${}_{xy}$ and s${}_{\pm }$ Pairing Symmetries in Superconducting La${}_3$Ni${}_2$O${}_7$ emerge from LDA+FLEX Calculations
• Effective model and pairing tendency in bilayer Ni-based superconductor La${}_3$Ni${}_2$O${}_7$
• Sensitive dependence of pairing symmetry on Ni-$e_g$ crystal field splitting in the nickelate superconductor La${}_3$Ni${}_2$O${}_7$
• Hund electronic correlation in La${}_3$Ni${}_2$O${}_7$ under high pressure
• Quantum Monte Carlo Study of Pairing Symmetry and Correlation in Iron-based Superconductors
• Theory of magnetic excitations in multilayer nickelate superconductor La${}_3$Ni${}_2$O${}_7$
• Electronic structure, magnetic correlations, and superconducting pairing in the reduced Ruddlesden-Popper bilayer La${}_3$Ni${}_2$O${}_6$ under pressure: different role of $d_{3z^2-r^2}$ orbital compared with La${}_3$Ni${}_2$O${}_7$
• Correlated electronic structures and unconventional superconductivity in bilayer nickelate heterostructures
• Optical properties and electronic correlations in La${}_3$Ni${}_2$O${}_7$ bilayer nickelates under high pressure
• Superconductivity in the Bilayer Two-orbital Hubbard Model
• Electronic properties of nickelate superconductor R3Ni2O7 with oxygen vacancies
• Importance of ligand on-site interactions for the description of Mott-insulators in DFT+DMFT
• Explicit demonstration of the equivalence between DFT+U and the Hartree-Fock limit of DFT+DMFT
• Band Structure and Pairing Nature of La${}_3$Ni${}_2$O${}_7$ Thin Film at Ambient Pressure
• Transition from $s_{\pm }$-wave to $d_{x^2-y^2}$-wave superconductivity driven by interlayer interaction in the bilayer two-orbital model of La${}_3$Ni${}_2$O${}_7$
• Electronic structures and superconductivity in Nd-doped La${}_3$Ni${}_2$O${}_7$
• General trends of electronic structures, superconducting pairing, and magnetic correlations in the Ruddlesden-Popper nickelate $m$-layered superconductors La${}_{m+1}$Ni${}_m$O${}_{3m+1}$
• The competition between antiferromagnetism and superconductivity in a doped Hubbard model with anisotropic interaction
• Extended $s$-wave pairing from an emergent Feshbach resonance in bilayer nickelate superconductors
• Parameters dependent superconducting transition temperature in high temperature superconductors

Cited by in corpus (2)

• Compressive Strain Turns $s^{\pm }$ into $d$-Wave Pairing in One-unit-cell La${}_3$Ni${}_2$O${}_7$ Thin Film Via Substrate-Induced Hole Doping
• Tuning superconducting pairing symmetry via a staggered potential in the doped honeycomb Hubbard model