Daily Overview: The highlighted work today focuses on achieving an in-depth understanding of the electronic structure of mixed-type Ruddlesden-Popper nickelates. Using high-resolution angle-resolved photoemission spectroscopy combined with theoretical calculations, ref. [1] effectively isolated the intrinsic physics of the NiO layers in single-layer La1.4Sr0.6NiO4, revealing high-energy kinks and orbital-dependent band renormalization under strong electron correlations, and observing flat Fermi surface sheets along the diagonal direction in momentum space and a quasi-one-dimensional electronic structure. This square Fermi surface topology further gives rise to non-Fermi-liquid behavior, whose power-law spectral function, robust temperature scaling, and spin-charge separation characteristics are consistent with the Luttinger liquid model. This work demonstrates that exotic Luttinger liquid behavior can emerge in intrinsic quasi-two-dimensional nickel oxides due to an unexpected dimensional reduction, providing a new perspective for understanding the physics of multilayer nickel oxides and the electronic states associated with nickel-based superconductivity. arXiv submission processing window: 2026-10-07 00:00 to 2026-10-07 00:00 UTC.

1. Luttinger Liquid Behavior in a Single-Layer Nickelate La1.4Sr0.6NiO4

  • Relevance Score: 5.6160
  • Authors: Yinqi Hu, Yidian Li, Xian Du, Wenxuan Zhao, Kaiyi Zhai, Senyao Zhang, Jiawei Shao, Mingxin Mao, Houke Chen, Jieyi Liu, Donghui Lu, Makoto Hashimoto, Fangyuan Zhu, Zhengtai Liu, Dawei Shen, Yaobo Huang, Zhongkai Liu, D. Prabhakaran, Yanpeng Qi, Yilin Wang, Yulin Chen, Lexian Yang
  • Affiliations: ShanghaiTech Laboratory for Topological Physics, Chinese Academy of Sciences, University of Science and Technology of China, University of Oxford, Yale University, Diamond Light Source, SLAC National Accelerator Laboratory, Frontier Science Center for Quantum Information, ShanghaiTech University, Tsinghua University
  • Link: https://arxiv.org/abs/2610.07656
  • Paper page: Luttinger Liquid Behavior in a Single-Layer Nickelate La₁.₄Sr₀.₆NiO₄

Summary: Using high-resolution angle-resolved photoemission spectroscopy combined with theoretical calculations, this work systematically investigates the single-layer Ruddlesden-Popper nickelate La1.4Sr0.6NiO4 to isolate the intrinsic physics of the NiO layers. The results reveal strong electron correlations, manifested as high-energy kinks in the band dispersion and pronounced orbital-dependent band renormalization; flat Fermi surface sheets are also observed along the diagonal momentum direction, forming a quasi-one-dimensional electronic structure. This square Fermi surface topology gives rise to non-Fermi liquid behavior consistent with the Luttinger liquid model, as evidenced by power-law spectral functions, robust temperature scaling, and spin-charge separation. The study reveals exotic Luttinger liquid behavior emerging from an unexpected dimensional reduction in an intrinsic quasi-two-dimensional nickelate and provides a new perspective for understanding the physics of multilayer nickelates.