Daily Overview: This post sorts papers by relevance to nickelate superconductors. Summaries are AI-generated and may contain errors. arXiv submission processing window: times are unavailable (UTC).
1. Collective spin excitations in trilayer nickelate La$_4$Ni$_3$O$_{10}$
- Relevance Score:
5.2877 - Authors: Ying Chan, Yuehong Li, Yujie Yan, Xunyang Hong, Tianren Wang, Marli dos Reis Cantarino, Yinghao Zhu, Enkang Zhang, Lixing Chen, Jun Okamoto, Hsiao-Yu Huang, Di-Jing Huang, N. B. Brookes, Johan Chang, Yao Shen, Jun Zhao, Qisi Wang
- Link: http://arxiv.org/abs/2604.04643v1
- Paper page: Collective spin excitations in trilayer nickelate La₄Ni₃O₁₀
Summary: Resonant inelastic X-ray scattering (RIXS) at the Ni L edge on single crystals of the trilayer nickelate La4Ni3O10 reveals collective spin excitations with a bandwidth of approximately 60 meV, comparable to that of the bilayer nickelate La3Ni2O7, but with significantly reduced spectral weight, indicating weaker electronic correlations in the trilayer system. Localized spin excitations at around 100 and 200 meV are also observed, originating from local dipole and quadrupole excitations. The dispersive magnetic excitations exhibit three-dimensional characteristics, and fitting with linear spin-wave theory yields comparable in-plane and out-of-plane exchange coupling parameters, with the interlayer coupling being the strongest. The results indicate that La4Ni3O10 possesses stronger three-dimensional magnetism, with its spin dynamics consistent with spin-density-wave order, while the reduced electronic correlations and three-dimensional multi-orbital character are key factors leading to differences in its magnetic excitation spectrum compared to the bilayer nickelate, providing important insights into the evolution of magnetism and its connection to superconductivity in the Ruddlesden-Popper nickelate family.
2. Multimodal Terahertz Spectroscopy of the Pairing Symmetry and Normal-State Pseudogap in (La,Pr)$_3$Ni$_2$O$_7$ Films
- Relevance Score:
5.1288 - Authors: Shuxiang Xu, Guangdi Zhou, Hao Wang, Tianyi Wu, Wei Wang, Liyu Shi, Dong Wu, Haoliang Huang, Xinbo Wang, Jinfeng Jia, Qi-Kun Xue, Zhuoyu Chen, Tao Dong, Nanlin Wang
- Affiliations: Southern University of Science and Technology, Tsinghua University, Beijing Academy of Quantum Information Sciences, Peking University, Chinese Academy of Sciences, Shanghai Jiao Tong University, Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area, Center for High Pressure Science and Technology Advanced Research
- Link: http://arxiv.org/abs/2604.04421v1
- Paper page: Multimodal Terahertz Spectroscopy of the Pairing Symmetry and Normal-State Pseudogap in (La,Pr)₃Ni₂O₇ Films
Summary: By combining linear terahertz time-domain spectroscopy with third-harmonic generation, this study systematically probes the superconducting pairing symmetry and normal-state pseudogap in compressively strained (La,Pr)₃Ni₂O₇ thin films. Linear terahertz spectroscopy reveals a significant suppression of low-frequency spectral weight below the superconducting transition temperature, accompanied by a weak coherence peak and a large residual conductivity persisting down to near-zero temperature, consistent with a disordered s±-wave pairing scenario. The nonlinear third-harmonic signal sharply enhances upon entering the superconducting state, but its response persists above the superconducting transition temperature, exhibiting a kink at approximately 100 K, which is attributed to the normal-state pseudogap based on similar temperature scales observed in angle-resolved photoemission spectroscopy on analogous films. This study establishes (La,Pr)₃Ni₂O₇ as a bulk superconductor with s±-wave-like pairing, where superconductivity coexists and likely competes with another ordered state, providing a new platform for exploring unconventional superconducting mechanisms beyond cuprates and iron-based superconductors.