2026-10-20 合肥物質科学研究院（HFIPS）
(a) Crystal structure of La2NiO4, with blue polyhedra representing NiO6 octahedra. (b) G-type AFM arrangement; arrows indicate the Ni spin directions. (c, d) Orbital-projected band structures at 0 and 50 GPa, respectively. The red dashed line marks the Fermi level. The band gap closes near 50 GPa. (Image by WANG Hanyu)
＜関連情報＞
- https://english.hf.cas.cn/nr/rn/202610/t20261020_1208626.html
- https://journals.aps.org/prb/abstract/10.1103/9736-nl72
ラドルスデン・ポッパーにおける磁気秩序と金属化の圧力およびドーピング制御La2NiO4 Pressure and doping control of magnetic order and metallization in Ruddlesden-Popper La2NiO4
Han-Yu Wang, Shu-Hong Tang, Xiao-Teng Huang,, Ya-Min Quan, Xian-Long Wang, Yan-Ling Li, Hao Chen, Da-Yong Liu, Hai-Qing Lin et al.
Physical Review B Published: 14 September, 2026
DOI: https://doi.org/10.1103/9736-nl72
Abstract
The discovery of superconductivity in multilayer nickelates under pressure has intensified interest in understanding the magnetic and electronic properties of Ruddlesden-Popper nickelates. Using density functional theory with Hubbard corrections, we investigate the magnetic ground state, electronic structure evolution under pressure, and Sr-doping effects in La2NiO4. We find that at ambient pressure, tetragonal La2NiO4 exhibits -type antiferromagnetic order with negligible interlayer magnetic coupling. Under hydrostatic pressure, the system undergoes a continuous insulator-metal transition at 50 GPa while maintaining robust magnetic order, contrasting sharply with the rapid magnetic suppression in La3Ni2O7. Sr doping leads to a sequence of magnetic ground states in our calculations: from type to type, to striped antiferromagnetic orders, and, eventually, to ferromagnetic order, accompanied by metallization. Furthermore, LaSrNiO4 displays weak charge and orbital orders. These results reveal the unique pressure and doping effects of single-layer nickelates and provide insights into the magnetic mechanisms underlying nickelate superconductivity.
