Synthesis and characterisation of LK-99

Ivan Timokhin; Chuhongxu Chen; Ziwei Wang; Qian Yang; Artem Mishchenko

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arXiv · 2308.03823

Synthesis and characterisation of LK-99

Ivan Timokhin·Chuhongxu Chen·Ziwei Wang·Qian Yang·Artem Mishchenko

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Abstract

Recently, two arXiv preprints (arXiv:2307.12008, arXiv:2307.12037) reported signatures of superconductivity above room temperature (SART) and at ambient pressure, striking worldwide experimental research efforts in replicating the results3-6, as well as theoretical attempts to explain the purported superconductivity7-11. The material of interest has chemical formula Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O, where $x \approx 1$, and was named by the authors as LK-99. It belongs to lead apatite family, and was synthesised from two precursors, lanarkite (PbSO$_4\cdot$PbO) and copper phosphide (Cu$_3$P). Here we performed a systematic study on LK-99, starting from solid-state synthesis, followed by characterisation and transport measurements. We did not observe any signatures of superconductivity in our samples of LK-99.

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Ivan Timokhin, Chuhongxu Chen, Ziwei Wang, Qian Yang, Artem Mishchenko. 2023-08-07. Synthesis and characterisation of LK-99. https://arxiv.org/abs/2308.03823

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