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arXiv · 2311.11122

Is La3Ni2O6.5 a Bulk Superconducting Nickelate?

Ran Gao·Lun Jin·Shuyuan Huyan·Danrui Ni·Haozhe Wang·Xianghan Xu·Sergey L. Budko·Paul Canfield·Weiwei Xie·Robert J. Cava
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Abstract

Superconducting states onsetting at moderately high temperatures have been observed in epitaxially-stabilized RENiO2-based thin films. However, recently it has also been reported that superconductivity at high temperatures is observed in bulk La3Ni2O7-{\delta} at high pressure, opening further possibilities for study. Here we report the reduction profile of La3Ni2O7 in a stream of 5% H2/Ar gas and the isolation of the metastable intermediate phase La3Ni2O6.45, which is based on Ni2+. Although this reduced phase does not superconduct at ambient or high pressures, it offers insights into the Ni-327 system and encourages the future study of nickelates as a function of oxygen content.

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Ran Gao, Lun Jin, Shuyuan Huyan, Danrui Ni, Haozhe Wang, Xianghan Xu, Sergey L. Budko, Paul Canfield, Weiwei Xie, Robert J. Cava. 2023-11-18. Is La3Ni2O6.5 a Bulk Superconducting Nickelate?. https://doi.org/10.1021/acsami.3c17376

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