Single crystal synthesis, structure, and magnetism of Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O

P. Puphal; M. Y. P. Akbar; M. Hepting; E. Goering; M. Isobe; A. A. Nugroho; B. Keimer

doi:10.1063/5.0172755

paper

Single crystal synthesis, structure, and magnetism of Pb $_{10 - x}$ Cu $_{x}$ (PO $_{4}$ ) $_{6}$ O

arXiv:2308.06256 · doi:10.1063/5.0172755

Abstract

The recent claim of superconductivity above room temperature in Pb $_{10 - x}$ Cu $_{x}$ (PO $_{4}$ ) $_{6}$ O with 0.9 < $x$ < 1 (referred to as LK-99) has sparked considerable interest. To minimize the influence of structural defects and impurity phases on the physical properties, we have synthesized phase-pure single crystals with $x \sim 1$ . We find that the crystals are highly insulating and optically transparent. X-ray analysis reveals an uneven distribution of the substituted Cu throughout the sample. Temperature ( $T$ ) dependent magnetization measurements for $2 \leq T \leq 800$ K reveal the diamagnetic response characteristic of a non-magnetic insulator, as well as a small ferromagnetic component, possibly originating from frustrated exchange interactions in Cu-rich clusters in the Pb $_{10 - x}$ Cu $_{x}$ (PO $_{4}$ ) $_{6}$ O structure. No anomalies indicative of phase transitions are observed. We therefore rule out the presence of superconductivity in Pb $_{9}$ Cu(PO $_{4}$ ) $_{6}$ O crystals, and provide some considerations on the origin of anomalies previously reported in experiments on polycrystalline specimen.

Single crystal synthesis, structure, and magnetism of Pb $_{10 - x}$ Cu $_{x}$ (PO $_{4}$ ) $_{6}$ O

Abstract

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Cited by in corpus (8)

Single crystal synthesis, structure, and magnetism of Pb10−x​Cux​(PO4​)6​O

Abstract

References in corpus (12)

Cited by in corpus (8)

Single crystal synthesis, structure, and magnetism of Pb $_{10 - x}$ Cu $_{x}$ (PO $_{4}$ ) $_{6}$ O