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arXiv · 2204.08050

Synthesis and Properties of La$_{1-x}$Sr$_x$NiO$_3$ and La$_{1-x}$Sr$_x$NiO$_2$

Mengwu Huo·Zengjia Liu·Hualei Sun·Lisi Li·Hui Lui·Chaoxin Huang·Feixiang Liang·Bing Shen·Meng Wang
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Abstract

Superconductivity has been realized in films of La$_{1-x}$Sr$_x$NiO$_2$. Here we report synthesis and characterization of polycrystalline samples of La$_{1-x}$Sr$_x$NiO$_3$ and La$_{1-x}$Sr$_x$NiO$_2$ ($0\le x\le 0.2$). Magnetization and resistivity measurements reveal that La$_{1-x}$Sr$_x$NiO$_3$ are paramagnetic metals and La$_{1-x}$Sr$_x$NiO$_2$ exhibit insulating behavior. Superconductivity is not detected in bulk samples of La$_{1-x}$Sr$_x$NiO$_2$. The absence of superconductivity in bulk La$_{1-x}$Sr$_x$NiO$_2$ may be due to the generation of hydroxide during reduction or a small amount of nickel impurities. The effect of interface in films of La$_{1-x}$Sr$_x$NiO$_2$ may also play a role for superconductivity.

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Mengwu Huo, Zengjia Liu, Hualei Sun, Lisi Li, Hui Lui, Chaoxin Huang, Feixiang Liang, Bing Shen, Meng Wang. 2022-04-17. Synthesis and Properties of La$_{1-x}$Sr$_x$NiO$_3$ and La$_{1-x}$Sr$_x$NiO$_2$. https://doi.org/10.1088/1674-1056/ac7a1a

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