来源 自动抓取
作者 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
arXiv / 出版方 http://arxiv.org/abs/2604.04643v1
PDF https://arxiv.org/pdf/2604.04643v1
相关度评分 5.288
主分类 本批次暂无数据。
发布日期 本批次暂无数据。
研究范式 实验研究
样品形态 单晶

摘要

通过Ni L边共振非弹性X射线散射（RIXS）对三镍酸盐La4Ni3O10单晶的研究，发现其集体自旋激发具有约60 meV的带宽，与双层镍酸盐La3Ni2O7相当，但谱权重显著降低，表明三镍酸盐中电子关联较弱。同时观察到约100和200 meV的局域自旋激发，源自局域偶极和四极激发。分散的磁激发表现出三维特征，利用线性自旋波理论拟合得到层内与层间交换耦合参量相当，其中层间耦合最强。结果表明La4Ni3O10具有更强的三维磁性，其自旋动力学与自旋密度波序一致，而电子关联的减弱和三维多轨道特性是导致其磁激发谱与双层镍酸盐差异的关键因素，为理解Ruddlesden-Popper镍酸盐家族中磁性的演化及其与超导性的关联提供了重要见解。

材料

方法

关键词

  • collective spin excitations
  • spin density wave
  • three dimensional magnetism
  • exchange coupling

亮点

  • Localized spin excitations at around 100 and 200 meV originate from local dipole and quadrupole excitations.
  • The interlayer coupling is the strongest exchange parameter, pointing to enhanced three-dimensional magnetism.

结论

  • Collective spin excitations in La4Ni3O10 have a bandwidth of about 60 meV but significantly reduced spectral weight compared to La3Ni2O7, indicating weaker electronic correlations.
  • The magnetic excitations exhibit three-dimensional characteristics with comparable in-plane and out-of-plane exchange couplings.

主要论断

  • Collective spin excitations in La4Ni3O10 have comparable bandwidth (≈60 meV) to La3Ni2O7 but significantly reduced spectral weight
    • 证据: RIXS measurements show dispersive excitations with zone boundary energy ≈60 meV,Spectral weight is nearly an order of magnitude weaker than in La3Ni2O7
  • La4Ni3O10 exhibits stronger three-dimensional magnetism with comparable in-plane and out-of-plane exchange couplings
    • 证据: LSWT fits yield J_in=46 meV, J_out=34 meV, J_⊥=62 meV,Dispersive excitations are three-dimensional

研究流程

  • Sample growth and characterization
    • 材料: La4Ni3O10 single crystals
    • 方法: High-pressure optical floating zone method; X-ray diffraction
  • RIXS measurements — Collective spin excitations with 60 meV bandwidth observed
    • 材料: Ni L-edge RIXS at ID32 and 41A1
    • 方法: RIXS with polarization analysis; Energy resolution ≈40 meV
    • 观察: Localized spin excitations at ≈100 meV and ≈200 meV; Dispersive excitation at ≈60 meV
  • Modeling — Three-dimensional magnetism with strongest interlayer coupling
    • 方法: Linear spin-wave theory (LSWT); Single-ion exact diagonalization
    • 观察: Intra- and inter-layer exchange couplings: J_in=46 meV, J_out=34 meV, J_⊥=62 meV