Epitaxial growth of Ruddlesden-Popper neodymium nickelates Nd$_{n+1}$Ni$_{n}$O$_{3n+1}$ (${n}$ = 1-5)

Wenjie Sun; Yueying Li; Xiangbin Cai; Jiangfeng Yang; Wei Guo; Zhengbin Gu; Ye Zhu; Yuefeng Nie

doi:10.1103/physrevb.104.184518

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arXiv · 2106.12941

Epitaxial growth of Ruddlesden-Popper neodymium nickelates Nd$_{n+1}$Ni$_{n}$O$_{3n+1}$ (${n}$ = 1-5)

Wenjie Sun·Yueying Li·Xiangbin Cai·Jiangfeng Yang·Wei Guo·Zhengbin Gu·Ye Zhu·Yuefeng Nie

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Abstract

A series of Ruddlesden-Popper nickelates, Nd$_{n+1}$Ni$_{n}$O$_{3n+1}$ (${n}$ = 1-5), have been stabilized in thin film form using reactive molecular-beam epitaxy. High crystalline quality has been verified by X-ray diffraction and scanning transmission electron microscopy. X-ray photoelectron spectroscopy indicates the ${n}$-dependent valence states of nickel in these compounds. Metal-insulator transitions show clear ${n}$ dependence for intermediate members (${n}$ = 3-5), and the low-temperature resistivities of which show logarithmic dependence, resembling the Kondo-scattering as observed in the parent compounds of superconducting infinite-layer nickelates.

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Wenjie Sun, Yueying Li, Xiangbin Cai, Jiangfeng Yang, Wei Guo, Zhengbin Gu, Ye Zhu, Yuefeng Nie. 2021-06-24. Epitaxial growth of Ruddlesden-Popper neodymium nickelates Nd$_{n+1}$Ni$_{n}$O$_{3n+1}$ (${n}$ = 1-5). https://doi.org/10.1103/physrevb.104.184518

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