Superconducting Instabilities in Strongly Correlated Infinite-Layer Nickelates

Physical Review Letters, Journal Year: 2022, Volume and Issue: 129(7)

Published: Aug. 11, 2022

The discovery of superconductivity in infinite-layer nickelates has added a new family materials to the fascinating growing class unconventional superconductors. By incorporating strongly correlated multiorbital nature low-energy electronic degrees freedom, we compute leading superconducting instability from magnetic fluctuations relevant for nickelates. Specifically, by properly including doping dependence Ni d_{x^{2}-y^{2}} and d_{z^{2}} orbitals as well self-doping band, uncover transition d-wave pairing symmetry nodal s_{±} superconductivity, driven strong d_{z^{2}}-dominated orbital states. We discuss properties resulting condensates light recent tunneling penetration depth experiments probing detailed gap structure these materials.

Language: Английский

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Superconducting Nd _{1− x} Eu _x NiO ₂ thin films using in situ synthesis

Science Advances, Journal Year: 2023, Volume and Issue: 9(27)

Published: July 5, 2023

We report on superconductivity in Nd 1− x Eu NiO 2 using as a 4f dopant of the parent NdNiO infinite-layer compound. use an all–in situ molecular beam epitaxy reduction process to achieve superconducting phase, providing alternate method ex CaH induce nickelates. The samples exhibit step-terrace structure their surfaces, have T c onset 21 K at = 0.25, and large upper critical field that may be related doping.

Language: Английский

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Optimizing Superconductivity: From Cuprates via Nickelates to Palladates

Physical Review Letters, Journal Year: 2023, Volume and Issue: 130(16)

Published: April 20, 2023

Motivated by cuprate and nickelate superconductors, we perform a comprehensive study of the superconducting instability in single-band Hubbard model. We calculate spectrum transition temperature T_{c} as function filling Coulomb interaction for range hopping parameters, using dynamical vertex approximation. find sweet spot high to be at intermediate coupling, moderate Fermi surface warping, low hole doping. Combining these results with first principles calculations, neither nickelates nor cuprates are close this optimum within description. Instead, identify some palladates, notably RbSr_{2}PdO_{3} A_{2}^{'}PdO_{2}Cl_{2} (A^{'}=Ba_{0.5}La_{0.5}), virtually optimal, while others, such NdPdO_{2}, too weakly correlated.

Language: Английский

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Superconductivity in an ultrathin multilayer nickelate

Science Advances, Journal Year: 2025, Volume and Issue: 11(1)

Published: Jan. 1, 2025

We report the appearance of superconductivity in single-unit-cell Nd 6 Ni 5 O 12 , exhibiting a transition temperature similar to that thicker films. In situ synchrotron x-ray scattering performed during growth parent phase, 16 shows necessary layer-by-layer deposition sequence does not follow formula unit but an alternate order due relative stability perovskite cell. exploit this insight grow ultrathin heterostructures and conduct studies topotactic reduction, finding formation square-planar phase occurs rapidly is highly sensitive reduction temperature, with small deviations from optimum condition leading inhomogeneity loss superconductivity. The fluorite layer within cell facilitates by initially stabilizing upper half Our findings provide into Ruddlesden-Popper nickelates, highlighting need for metastable phases key

Language: Английский

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Two-Gap Superconductivity and the Decisive Role of Rare-Earth d Electrons in Infinite-Layer Nickelates

Physical Review Letters, Journal Year: 2024, Volume and Issue: 133(12)

Published: Sept. 17, 2024

We present a theoretical prediction of phonon-mediated two-gap superconductivity in infinite-layer nickelates Nd_{1-x}Sr_{x}NiO_{2} by performing ab initio GW and perturbation theory calculations. Electron self-energy effects significantly alter the characters two-band Fermi surface enhance electron-phonon coupling, compared with results based on density functional theory. Solutions fully k-dependent anisotropic Eliashberg equations yield two dominant s-wave superconducting gaps-a large gap band rare-earth Nd d interstitial orbital small transition-metal Ni character. Increasing hole doping induces non-rigid-band response electronic structure, leading to rapid drop T_{c} overdoped regime agreement experiments.

Language: Английский

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Orbital-Nematic and Two-Fluid Superconductivity in Hole-Doped NdNiO2

Condensed Matter, Journal Year: 2025, Volume and Issue: 10(1), P. 18 - 18

Published: March 14, 2025

Based on DFT + DMFT, we investigate the orbital-nematic and s-wave superconducting states of a hole-doped NdNiO2 superconductor. We emphasize role played by interorbital proximity effect in determining orbital-selective electronic state both normal phases. Specifically, show how plus pairing symmetry acting xz orbital might have pronounced effects proximitized non-superconducting Ni-3d orbitals due to many-particle electron–electron interactions. This work represents step forward understanding emergence two-fluid superconductivity (with xy,yz,x2−y2,3z2−r2 channels) superconductors.

Language: Английский

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Low-energy interband Kondo bound states in orbital-selective Mott phases

Physical review. B./Physical review. B, Journal Year: 2025, Volume and Issue: 111(15)

Published: April 3, 2025

Language: Английский

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Rare-earth control of phase transitions in infinite-layer nickelates

PNAS Nexus, Journal Year: 2023, Volume and Issue: 2(5)

Published: March 29, 2023

Abstract Perovskite nickelates RNiO3 (R = rare-earth ion) exhibit complex ion dependent phase diagram and high tunability of various appealing properties. Here, combining first- finite-temperature second-principles calculations, we explicitly demonstrate that the superior merits interplay among lattice, electron, spin degrees freedom can be passed to RNiO2, which recently gained significant interest as superconductors. We unveil decreasing size directly modulates structural, electronic, magnetic properties naturally groups infinite-layer into two categories in terms Fermi surface dimensionality: compounds with large sizes (La, Pr) closely resemble key CaCuO2, showing quasi-two-dimensional (2D) antiferromagnetic (AFM) correlations strongly localized dx2−y2 orbitals around level; small (Nd–Lu) are highly analogous ferropnictides, three-dimensional (3D) dimensionality strong kz dispersion d3z2−r2 electrons at level. Additionally, highlight RNiO2 R Nd–Lu on cooling a structural transition appearance oxygen rotation motion, is softened by reduction enhanced spin-rotation couplings. The control might factors differentiating distinct upper critical field resistivity different compounds. established original summarizing temperature controlled transitions provides rich chemical flexibility tailor superconducting property.

Language: Английский

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Quantifying interaction mechanism in infinite layer nickelate superconductors

Journal of Applied Physics, Journal Year: 2023, Volume and Issue: 134(11)

Published: Sept. 19, 2023

The connection between the long-range antiferromagnetic order in cuprates and high-temperature superconductivity is a scientific problem that has yet to be solved after nearly four decades. properties difficulties of describing nickelate superconductors are similar those cuprates. Recently, Fowlie et al. [Nat. Phys. 18, 1043 (2022)] aimed detect R1−xSrxNiO2 (R = Nd, Pr, La; x ∼ 0, 0.2) films by using muon spin rotation (μSR) technique. research group reported presence short-range every studied. Here, our goal was prove this interaction present films. We did analyzing temperature dependent resistivity, ρ(T), data from group. Global ρ(T) fits advanced Bloch–Grüneisen model showed each compounds can characterized unique power-law exponent, p (where 2 for electron–electron scattering, 3 electron–magnon 5 electron–phonon scattering), global characteristic temperature, Tω (which meaning Debye at 5). found 2.0 Nd- Pr-based 1.3 La-based compounds. latter value does not have any interpretation within established theoretical models. also analyzed Nd1–xSrxNiO2(0.125≤x≤0.325) Lee [Nature 619, 288 (2023)]. Our analysis nickelates led us conclude new needed describe materials exhibiting order.

Language: Английский

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Charge ordering as the driving mechanism for superconductivity in rare-earth nickel oxides

Physical Review Materials, Journal Year: 2024, Volume and Issue: 8(6)

Published: June 4, 2024

Superconductivity is one of the most intriguing properties matter, described by an attractive interaction that binds electrons into Cooper pairs. To date, highest critical temperature at ambient conditions achieved in copper oxides. While layered nickel oxides were long proposed to be analogous cuprates, superconductivity was only demonstrated 2019 albeit without clarifying pairing mechanism. Here we use density functional theory show nickelates driven electron-phonon coupling originating from a charge ordering. Due intrinsic electronic instability half-doped compounds, $\mathrm{N}{\mathrm{i}}^{1.5+}$ cations dismutate more stable $\mathrm{N}{\mathrm{i}}^{+}$ and $\mathrm{N}{\mathrm{i}}^{2+}$ cations, which accompanied bond disproportionation $\mathrm{Ni}{\mathrm{O}}_{4}$ complexes producing insulating charge-ordered state. Once doping suppresses instability, vibration sufficient reproduce key characteristic observed experimentally, notably dome ${T}_{c}$ as function content. These phenomena are identified if relevant degrees freedom well exchange-correlation sufficiently amends self-interaction errors involved simulations. Finally, despite presence correlation effects inherent $3d$ elements favor formation local Ni spins, mechanism behind pairs nickelate superconductors appears similar nonmagnetic bismuth oxide superconductors.

Language: Английский

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