新加坡国立大学A. Ariando团队研究了常压下掺空穴SmNiO₂中40K附近的体超导电性。2025年3月20日出版的《自然》杂志发表了这项成果。

Ba-La-Cu-O系统（铜酸盐）在30 K范围内的超导性的发现标志着一个重大突破，这激发了对氧化物基层状超导体的广泛探索，以确定具有更高临界温度（T_c）的电子配对。尽管最近对氧化镍基化合物（镍酸盐）的超导性进行了观察，但在与铜酸盐同构但没有铜、环境压力和晶格压缩的系统中，30 K以上库珀配对的证据仍然难以捉摸。

研究组报告了d^9-x空穴掺杂的晚稀土无限层氧化镍（Sm-Eu-Ca-Sr）NiO₂薄膜在环境压力下T_c接近40 K的超导性，晶格压缩可以忽略不计，这得到了31 K下零电阻状态和迈斯纳效应的观测结果的支持。该材料可以合成，基本上没有Ruddlesden-Popper型结构缺陷，表现出约0.01 mΩ?cm的超低电阻率，残余电阻率比高达10。

该研究结果表明，使用铜以外的强相关d电子金属氧化物作为超导性的构建块，可以实现高温超导性，为进一步探索和理解高温库珀配对提供了一个有前景的平台。

附：英文原文

Title: Bulk superconductivity near 40 K in hole-doped SmNiO2 at ambient pressure

Author: Chow, S. Lin Er, Luo, Zhaoyang, Ariando, A.

Issue&Volume: 2025-03-20

Abstract: The discovery of superconductivity in the Ba-La-Cu-O system (the cuprate) in the 30 K range marked a significant breakthrough, which inspired extensive explorations of oxide based layered superconductors to identify electron pairing with higher critical temperatures (Tc)1. Despite recent observations of superconductivity in nickel-oxide-based compounds (the nickelates), evidence of Cooper pairing above 30 K in a system that is isostructural to the cuprates, but without copper, at ambient pressure and without lattice compression, has remained elusive2–5. Here, we report superconductivity with a Tc approaching 40 K under ambient pressure in the d9-x hole-doped, late rare-earth infinite-layer nickel oxide (Sm-Eu-Ca-Sr)NiO2 thin films with negligible lattice compression, supported by observations of a zero resistance state at 31 K and the Meissner effect. The material can be synthesized with essentially no Ruddlesden–Popper type structural defects, exhibiting ultralow resistivity of ~ 0.01 mΩcm with a residual-resistivity-ratio of up to 10. Our findings demonstrate the potential of achieving high-temperature superconductivity using strongly correlated d-electron metal oxides beyond copper as the building blocks for superconductivity, offering a promising platform for further exploration and understanding of high-temperature Cooper pairing.

DOI: 10.1038/s41586-025-08893-4

Source: https://www.nature.com/articles/s41586-025-08893-4