Paper

Daily Overview: Today’s highlights focus on deepening the understanding of the electronic structure of hybrid Ruddlesden-Popper nickelates. In [1], effective regulation of hole carriers was achieved through Na doping of La₃Ni₂O₇₊δ, significantly enhancing metallicity and suppressing the density wave transition, providing key experimental evidence for understanding the role of element substitution in stabilizing the high-pressure superconducting phase. Using soft X-ray absorption spectroscopy combined with theoretical calculations, [2] systematically tracked the topological reduction process from perovskite to infinite-layer nickelates, revealing that even in the most reduced films, the Ni 3d hole count remains as high as 1.35, and O 2p holes persist throughout. This challenges the simple hole-injection model of superconductivity, highlighting a complex synergistic mechanism involving self-doping and oxygen non-stoichiometry. Additionally, [3] rigorously examined the common method of estimating superconducting volume fractions based on internal magnetic susceptibility, pointing out that non-uniform distribution of the demagnetization factor can lead to significant overestimation, offering an important methodological caution for determining bulk superconductivity in systems such as Pr₄Ni₃O₁₀. arXiv submission processing window: 2026-03-10 00:00 to 2026-03-10 00:00 UTC. ...

arXiv Daily: nickelate superconductors 2026-03-10

Daily Overview: — Greetings, dear readers, and welcome to today’s rapid overview of research in the field of nickel-based superconductors. Today’s highlights focus on the electronic structure and superconducting mechanisms of mixed Ruddlesden-Popper nickelates and infinite-layer nickelates. In [1], through fluctuation exchange approximation analysis, it is found that hole doping in La₃Ni₂O₇ thin films can enhance the Fermi surface nesting-driven s±-wave pairing, providing a theoretical pathway for raising the superconducting transition temperature. In [2], systematic measurements of the superfluid density in Nd₁₋ₓSrₓNiO₂ thin films reveal the critical role of phase fluctuations in limiting the critical temperature, and uncover a strong coupling between the Nd 4f magnetic moments and the superfluid, with two-dimensional BKT behavior dominating the superconducting transition. These findings deepen our understanding of the pairing mechanisms and superfluid response in these two types of nickel-based superconductors. arXiv submission processing window: 2026-03-09 00:00 to 2026-03-09 00:00 UTC. ...

arXiv Daily: nickelate superconductors 2026-03-09

Daily Overview: Today’s highlights focus on the optimization of Ruddlesden-Popper nickelate thin film preparation and the discovery of unconventional superconductivity. In [1], the research team successfully fabricated phase-pure, high-quality Ln₃Ni₂O₇ thin films using giant oxidative atomic layer epitaxy, and systematically revealed the decisive role of four key factors—cation stoichiometry, atomic layer coverage, oxygen content, and interface reconstruction—on superconducting performance. The optimized films exhibited an onset transition temperature of up to 50 K, providing important guidance for the epitaxial growth of high-quality nickel-based superconducting thin films. In [2], through electrical transport measurements of (La, Pr, Sm)₃Ni₂O₇ bilayer nickelate thin films, time-reversal symmetry breaking superconductivity accompanied by electronic glass behavior was discovered for the first time, including features such as anomalous magnetoresistance hysteresis, nonreciprocal current-voltage response, and logarithmic slow relaxation. This finding offers groundbreaking phenomenological evidence and a conceptual framework for understanding the mechanism of nickel-based high-temperature superconductivity. arXiv submission processing window: 2026-03-05 00:00 to 2026-03-05 00:00 UTC. ...

arXiv Daily: nickelate superconductors 2026-03-05

Daily Overview: Today’s highlight focuses on an in-depth understanding of the electronic structure of hybrid Ruddlesden–Popper nickelates. [1] Using the fluctuation exchange approximation, the superconducting properties of a two-orbital model in La₃Ni₂O₇ thin films under ambient pressure are systematically analyzed. It reveals how hole-doping-induced Fermi surface nesting (between δ and γ pockets, as well as between α and β pockets) synergistically enhances s±-wave pairing, indicating that this nesting-driven spin fluctuation mechanism provides a feasible route to enhance ambient-pressure superconductivity in this system. arXiv submission processing window: 2026-03-04 00:00 to 2026-03-04 00:00 UTC. ...

arXiv Daily: nickelate superconductors 2026-03-04

Daily Overview: Today’s highlighted work focuses on an in-depth understanding of electron correlations, phase fluctuations, and experimental characterization methods in nickel-based superconductors. In [1], RIXS studies on La$_{3-x}$Sr$_x$Ni$_2$O$_7$ thin films reveal that double-stripe spin excitations remain robust within the superconducting dome but collapse sharply in the overdoped non-superconducting regime, directly establishing a link between magnetism and superconductivity. In [2], nano-patterning enhances phase fluctuations in Nd$_{0.8}$Sr$_{0.2}$NiO$_2$, leading to the observation of a two-stage superconducting transition, an anomalous metallic state, and an anisotropy reversal of the in-plane/out-of-plane critical fields, highlighting the potential of phase coherence engineering in strongly correlated systems. In [3], addressing the controversial estimation of the superconducting shielding volume fraction in pressurized Ruddlesden-Popper nickelates, it is clarified that the self-consistent method based on demagnetization factor correction is the standard and correct approach, while the linear assumption of the opposing party leads to an underestimation of the shielding fraction. These works advance the understanding of the mechanism and characterization of nickel-based superconductivity from the perspectives of spin excitations, quantum phase effects, and measurement methodology, respectively. arXiv submission processing window: 2026-03-03 00:00 to 2026-03-03 00:00 UTC. ...

arXiv Daily: nickelate superconductors 2026-03-03