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Absence of Superconductivity in LK-99 at Ambient Conditions

[Image: see text] The report of the synthesis of modified lead apatite (LK-99), with evidence of superconductivity at more than boiling water temperature, has steered the scientific community. There have been several failures to reproduce superconductivity in LK-99, despite partial successes. Here,...

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Autores principales: Kumar, Kapil, Kumar Karn, Navneet, Kumar, Yogesh, Awana, V.P.S.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2023
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10633996/
https://www.ncbi.nlm.nih.gov/pubmed/37969980
http://dx.doi.org/10.1021/acsomega.3c06096
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author Kumar, Kapil
Kumar Karn, Navneet
Kumar, Yogesh
Awana, V.P.S.
author_facet Kumar, Kapil
Kumar Karn, Navneet
Kumar, Yogesh
Awana, V.P.S.
author_sort Kumar, Kapil
collection PubMed
description [Image: see text] The report of the synthesis of modified lead apatite (LK-99), with evidence of superconductivity at more than boiling water temperature, has steered the scientific community. There have been several failures to reproduce superconductivity in LK-99, despite partial successes. Here, we have continued our efforts to synthesize phase-pure LK-99 with improved precursors. The synthesis process being followed is the same as suggested by Sukbae Lee et al. The phase purity of each precursor is evidenced by powder X-ray diffraction (PXRD) and is well-fitted by Rietveld refinement. The PXRD confirms the synthesis of phase-pure polycrystalline LK-99 with a lead apatite structure. The sample is highly resistive, showing insulator-like behavior in resistivity measurement in the temperature range from 215 to 325 K, which confirms the absence of superconductivity in synthesized LK-99 at room temperature. The magnetization measurements of LK-99 on the SQUID magnetometer resemble the behavior of a resistive diamagnetic material at 280 K. Moreover, we have also performed first principle calculations to investigate the electronic band structure of LK-99 in the vicinity of the Fermi level. Our study verifies that the copper (Cu)-doped lead apatite (LK-99) exhibits band crossing at the Fermi level, indicating the generation of strong correlation in the presently studied system. Our experimental results do not approve the appearance of superconductivity in LK-99, i.e., Pb(9)CuP(6)O(25).
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spelling pubmed-106339962023-11-15 Absence of Superconductivity in LK-99 at Ambient Conditions Kumar, Kapil Kumar Karn, Navneet Kumar, Yogesh Awana, V.P.S. ACS Omega [Image: see text] The report of the synthesis of modified lead apatite (LK-99), with evidence of superconductivity at more than boiling water temperature, has steered the scientific community. There have been several failures to reproduce superconductivity in LK-99, despite partial successes. Here, we have continued our efforts to synthesize phase-pure LK-99 with improved precursors. The synthesis process being followed is the same as suggested by Sukbae Lee et al. The phase purity of each precursor is evidenced by powder X-ray diffraction (PXRD) and is well-fitted by Rietveld refinement. The PXRD confirms the synthesis of phase-pure polycrystalline LK-99 with a lead apatite structure. The sample is highly resistive, showing insulator-like behavior in resistivity measurement in the temperature range from 215 to 325 K, which confirms the absence of superconductivity in synthesized LK-99 at room temperature. The magnetization measurements of LK-99 on the SQUID magnetometer resemble the behavior of a resistive diamagnetic material at 280 K. Moreover, we have also performed first principle calculations to investigate the electronic band structure of LK-99 in the vicinity of the Fermi level. Our study verifies that the copper (Cu)-doped lead apatite (LK-99) exhibits band crossing at the Fermi level, indicating the generation of strong correlation in the presently studied system. Our experimental results do not approve the appearance of superconductivity in LK-99, i.e., Pb(9)CuP(6)O(25). American Chemical Society 2023-10-25 /pmc/articles/PMC10633996/ /pubmed/37969980 http://dx.doi.org/10.1021/acsomega.3c06096 Text en © 2023 The Authors. Published by American Chemical Society https://creativecommons.org/licenses/by-nc-nd/4.0/Permits non-commercial access and re-use, provided that author attribution and integrity are maintained; but does not permit creation of adaptations or other derivative works (https://creativecommons.org/licenses/by-nc-nd/4.0/).
spellingShingle Kumar, Kapil
Kumar Karn, Navneet
Kumar, Yogesh
Awana, V.P.S.
Absence of Superconductivity in LK-99 at Ambient Conditions
title Absence of Superconductivity in LK-99 at Ambient Conditions
title_full Absence of Superconductivity in LK-99 at Ambient Conditions
title_fullStr Absence of Superconductivity in LK-99 at Ambient Conditions
title_full_unstemmed Absence of Superconductivity in LK-99 at Ambient Conditions
title_short Absence of Superconductivity in LK-99 at Ambient Conditions
title_sort absence of superconductivity in lk-99 at ambient conditions
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10633996/
https://www.ncbi.nlm.nih.gov/pubmed/37969980
http://dx.doi.org/10.1021/acsomega.3c06096
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