Superconductivity in Ruddlesden–Popper nickelates: a review of recent progress, focusing on thin films

Zhang, Yang [ORNL] (ORCID:0000000336235883); lin, Ling-Fang [University of Tennessee, Knoxville (UTK)]; Maier, Thomas [ORNL] (ORCID:0000000214249996); Dagotto Mir, Elbio [ORNL]

doi:10.1088/1361-6633/ae9aae

DOE OSTI · 3740500

Superconductivity in Ruddlesden–Popper nickelates: a review of recent progress, focusing on thin films

Zhang, Yang [ORNL] (ORCID:0000000336235883)·lin, Ling-Fang [University of Tennessee, Knoxville (UTK)]·Maier, Thomas [ORNL] (ORCID:0000000214249996)·Dagotto Mir, Elbio [ORNL]

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Abstract

The discovery of superconductivity with Tc ∼ 80 K in the nickelate Ruddlesden-Popper bilayer La3Ni2O7 at high pressure has opened a new platform for unconventional superconductivity, followed by the subsequent observation of superconductivity in trilayer La4Ni3O10, also at high pressure. Remarkably, ambient-pressure superconductivity was also observed recently in La3Ni2O7 ultra-thin films when grown on substrates that provide compressive strain. This discovery significantly extends the type of experimental techniques that can be used in nickelates, previously limited due to the high-pressure constraint. Discussing the similarities and differences among these nickel oxides will provide new insights into understanding the mechanism of high-Tc superconductivity in correlated electron systems. In this paper, we review the experimental and theoretical progress on Ruddlesden–Popper nickelates, with emphasis on thin films, and discuss future perspectives and research directions.

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Zhang, Yang [ORNL] (ORCID:0000000336235883), lin, Ling-Fang [University of Tennessee, Knoxville (UTK)], Maier, Thomas [ORNL] (ORCID:0000000214249996), Dagotto Mir, Elbio [ORNL]. 2026-09-01. Superconductivity in Ruddlesden–Popper nickelates: a review of recent progress, focusing on thin films. https://doi.org/10.1088/1361-6633/ae9aae

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