Microscopic characterization of Pb<sub>10-x</sub>Cu<sub>x</sub>(PO<sub>4</sub>)<sub>6</sub>O by <sup>31</sup>P, <sup>63</sup>Cu, and <sup>65</sup>Cu NMR measurements
ORAL
Abstract
The report of the first room-temperature ambient-pressure superconductivity in Pb10-xCux(PO4)6O has attracted lots of attention. However, the Meissner effect, which is a more decisive property of superconductors, has never been observed in this material. Later studies show that quite a lot of impurity phases exist in the polycrystalline samples, and the sharp superconducting-like transition is most likely due to a reduction in resistivity caused by the first-order structural phase transition of Cu2S at around 385 K, from the β phase at high temperature to the γ phase at low temperature. Till now, only bulk measurements have been performed on Pb10-xCux(PO4)6O samples, which would be easily affected by the impurity phases, and the intrinsic properties of Pb10-xCux(PO4)6O could be masked. Nuclear magnetic resonance(NMR) is a powerful technique to investigate the structural and magnetic properties of materials from a microscopic point of view. In this study, 31P, 63Cu, and 65Cu nuclear magnetic resonance (NMR) measurements have been performed on Pb10-xCux(PO4)6O powder sample. The structural and magnetic properties of Pb10-xCux(PO4)6O have been revealed.
*The research was supported by the U.S. Department of Energy (DOE), Office of Basic Energy Sciences, Division of Materials Sciences and Engineering. Ames National Laboratory is operated for the U.S. DOE by Iowa State University under Contract No. DE-AC02-07CH11358. This work was also partly supported by the National Key R&D Program of China (Grant No. 2018YFA0704300), the Strategic Priority Research Program (B) of the Chinese Academy of Sciences (Grant No. XDB25000000), and the National Natural Science Foundation of China (Grant No. U1932217).
–
Presenters
-
Qing-Ping Ding
- Ames National Laboratory
- Ames National Laboratory, U.S. DOE, and Department of Physics and Astronomy, Iowa State University