Systematic evolution of superconducting pairing strength and Seebeck coefficients in correlated infinite-layer La${}_{1-x}$Sr${}_x$NiO${}_2$

Abstract

The recently discovered superconducting infinite-layer nickelates offer a novel platform to explore an exotic pairing mechanism in multi-band systems towards high-temperature superconductivity and associated rich quantum phases, contrasting with cuprates. Here, we show that infinite-layer (La,Sr)NiO${}_2$ exhibits strong-coupling superconductivity, resilient to in-plane magnetic fields exceeding 47 T at optimal doping - more than twice the Pauli limit for conventional BCS superconductors. This violation becomes pronounced towards the underdoped regime, implying an intriguing evolution of pairing glue. The unexpected observation of positive Seebeck coefficients in this regime indicates the presence of nontrivial electron correlations. Furthermore, our comprehensive investigation across the superconducting dome reveals that the evolution of (thermo)electric normal-state properties - specifically, the sign changes of the Hall and Seebeck coefficients - coincide with the evolution of superconducting anisotropy and pairing strength. This demonstrates a definitive link between electron correlations and strong-coupling superconductivity in (La,Sr)NiO${}_2$, contributing to a unified framework for understanding unconventional superconductivity.

19 pages, 4 figures

References in corpus (35)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• The PseudoDojo: Training and grading a 85 element optimized norm-conserving pseudopotential table
• Wannier90 as a community code: new features and applications
• Quantum Criticality in Heavy Fermion Metals
• The virtual crystal approximation revisited: Application to dielectric and piezoelectric properties of perovskites
• Tunable Phase Boundaries and Ultra-Strong Coupling Superconductivity in Mirror Symmetric Magic-Angle Trilayer Graphene
• Superconductivity protected by spin-valley locking in ion-gated MoS2
• Spectral and Fermi surface properties from Wannier interpolation
• Electronic structure of the parent compound of superconducting infinite-layer nickelates
• Scattering and Pairing in Cuprate Superconductors
• Nickelate superconductivity without rare-earth magnetism: (La,Sr)NiO${}_2$
• "Pudding mold" band drives large thermopower in Na${}_x$CoO${}_2$
• Formation of 2D single-component correlated electron system and band engineering in the nickelate superconductor NdNiO2
• Model construction and a possibility of cuprate-like pairing in a new d9 nickelate superconductor (Nd,Sr)NiO2
• Nickelate superconductors -- a renaissance of the one-band Hubbard model
• Thermodynamic signatures of quantum criticality in cuprates
• Doping evolution of the Mott-Hubbard landscape in infinite-layer nickelates
• Fermi-surface reconstruction by stripe order in cuprate superconductors
• Mixed state properties of superconducting MgB2 single crystals
• Extremely strong coupling superconductivity in artificial two-dimensional Kondo lattices
• Character of the "normal state" of the nickelate superconductors
• Charge density waves in infinite-layer NdNiO${}_2$ nickelates
• Charge and spin order dichotomy in NdNiO${}_2$ driven by SrTiO${}_3$ capping layer
• Linear-in temperature resistivity from an isotropic Planckian scattering rate
• Superconducting Double Transition and the Upper Critical Field Limit of Sr2RuO4 in Parallel Magnetic Fields
• Absence of $3a_0$ Charge Density Wave Order in the Infinite Layer Nickelates
• Evidence for quasi-two-dimensional superconductivity in infinite-layer nickelates
• Determination of the Upper Critical Field of a Single Crystal LiFeAs: The Magnetic Torque Study up to 35 Tesla
• Seebeck coefficient in a cuprate superconductor: particle-hole asymmetry in the strange metal phase and Fermi surface transformation in the pseudogap phase
• Enhanced superconducting pairing strength near a nonmagnetic nematic quantum critical point
• Extraordinary $\pi$-Electron Superconductivity Emerging from a Quantum Spin Liquid
• Large upper critical fields and dimensionality crossover of superconductivity in infinite-layer nickelate La${}_{0.8}$Sr${}_{0.2}$NiO${}_2$
• Probing Quantum Confinement and Electronic Structure at Polar Oxide Interfaces
• Thermoelectric signature of quantum critical phase in a doped spin liquid candidate
• Quantitative assessment of the universal thermopower in the Hubbard model