Synteza wysokociśnieniowa poprawia właściwości nadprzewodzące PrFeAsO₁₋ₓFₓ

Prof. Shiv J. Singh’s research group at the Laboratory of Superconductors and Hydrogen Technologies (NL-6) is exploring high-pressure growth techniques for Pr-based oxypnictide superconductors. The group has recently published a new research article: “Effects of high-pressure synthesis on phase formation and superconducting properties of PrFeAsO1-xFx”, Physica C: Superconductivity and its Applications 650, 1354944 (2026) https://doi.org/10.1016/j.phys...

The study focuses on three representative compositions: underdoped (x = 0.2), optimal doped (x = 0.3), and overdoped (x = 0.5). The samples were processed using a high-pressure growth technique and compared with samples prepared by conventional synthesis at ambient pressure. The results show that high-pressure processing leads to improved densification and grain-to-grain connectivity, while also modifying phase formation and fluorine distribution. For the optimal doped x = 0.3 composition, the superconducting transition temperature increased by ~6 K after HP-HTS processing. The underdoped x = 0.2 composition showed a more modest increase of ~1 K, whereas the overdoped x = 0.5 composition exhibited a reduced superconducting response accompanied by increased secondary-phase formation. The study demonstrates that the superconducting properties following high-pressure synthesis are influenced by the combined effects of fluorine redistribution, phase evolution, microstructural densification, and grain connectivity. These findings provide new insights into the role of high-pressure synthesis in the processing and optimization of iron-based superconducting materials.

The results have been published in the following publication: Priya Singh, Konrad Kwatek, Tatiana Zajarniuk, Tomasz Cetner, Jan Mizeracki, and Shiv J. Singh, “Effects of high-pressure synthesis on phase formation and superconducting properties of PrFeAsO1-xFx”, Physica C: Superconductivity and its Applications 650, 1354944 (2026) https://doi.org/10.1016/j.phys...