Daily Overview: Today’s highlighted work focuses on an in-depth understanding of the electronic structure of mixed-type Ruddlesden-Popper nickelates, in which the normal-state transport behavior of trilayer Ruddlesden-Popper nickelates provides new clues for the physics of nickelate superconductivity. [1] Based on magnetoconductance quantum corrections in single crystals of Pr4Ni3O10 and La4Ni3O10, negative magnetoresistance and two-dimensional weak-localization signatures were observed at low temperatures, and the magnetoresistance scales with the perpendicular component of the magnetic field, indicating that in-plane transport lies in the quantum diffusion regime while out-of-plane transport is incoherent, and that the electronic ground state is approximately a quasi-two-dimensional disordered Fermi liquid. The weak localization remains relatively robust under a strong spin-orbit and magnetic background, arising from the partial cancellation between spin-orbit scattering and spin-flip scattering and from the spatial isolation of rare-earth ions from the NiO2 layers; pressurizing to 3 GPa continuously suppresses this feature, suggesting a two-dimensional/three-dimensional dimensional crossover and establishing a transport link between the ambient-pressure normal state and the pressure-induced superconducting state. Although these results are not direct superconducting measurements, they are of great significance for understanding the quasi-two-dimensional normal state, disorder effects, and pressure-tuned superconductivity in nickelates. arXiv submission processing window: 2026-09-14 00:00 to 2026-09-14 00:00 UTC.

1. 2D Weak Localization in Trilayer Ruddelsden-Popper Nickelates

Summary: By measuring quantum corrections to the magnetoconductance in single-crystal trilayer Ruddlesden-Popper nickelates Pr4Ni3O10 and La4Ni3O10, this study investigates their transport dimensionality, phase coherence, and scattering mechanisms. At low temperatures, negative magnetoresistance and two-dimensional weak localization (WL) signatures are observed, and the magnetoresistance scales with the perpendicular field component as a function of magnetic field orientation, indicating that in-plane electronic transport lies in the quantum diffusive regime, whereas out-of-plane transport is incoherent, with the electronic ground state being a quasi-two-dimensional disordered Fermi liquid. Despite the high atomic numbers of La/Pr and the magnetism of Ni/Pr, WL remains relatively robust, which arises from the partial cancellation of spin-orbit scattering and spin-flip scattering, as well as the spatial isolation of rare-earth ions from the NiO2 layers. Pressurizing to 3 GPa continuously suppresses the WL features, possibly indicating a two-dimensional/three-dimensional dimensional crossover and establishing a link between the ambient-pressure normal state and the pressure-induced superconducting state.