The Impact of Hydrogenation on Structural and Superconducting Properties of FeTe0.65Se0.35 Single Crystals

Materials

Anatolij I. Prokhvatilov¹  Valeriy P. Timofeev¹  Stanislav I. Bondarenko¹  Vladimir V. Meleshko¹  Valentin P. Koverya¹  Andrey A. Prokhorov²  Andrzej Wiśniewski³  Dariusz Jakub Gawryluk³  Jarosław Piętosa³  Roman Puźniak³ 

[1] B. Verkin Institute for Low Temperature Physics and Engineering, National Academy of Sciences of Ukraine, Nauky 47, 61103 Kharkov, Ukraine;Institute of Physics of the Czech Academy of Sciences, Na Slovance, 182 21 Prague 8, Czech Republic;Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland;

关键词: iron-based superconductors;    hydrogenation;    critical currents;    structural properties;   

DOI  :  10.3390/ma14247900

来源: DOAJ

【 摘 要 】

Properties of FeTe_0.65Se_0.35 single crystals, with the onset of critical temperature (T_c^onset) at 15.5 K, were modified via hydrogenation performed for 10–90 h, at temperatures ranging from 20 to 250 °C. It was found that the tetragonal matrix became unstable and crystal symmetry lowered for the samples hydrogenated already at 200 °C. However, matrix symmetry was not changed and the crystal was not destroyed after hydrogenation at 250 °C. Bulk T_c^bulk, determined at the middle of the superconducting transition, which is equal to 12–13 K for the as grown FeTe_0.65Se_0.35, rose by more than 1 K after hydrogenation. The critical current density studied in magnetic field up to 70 kOe increased 4–30 times as a consequence of hydrogenation at 200 °C for 10 h. Electron paramagnetic resonance measurements also showed higher values of T_c^bulk for hydrogenated crystals. Thermal diffusion of hydrogen into the crystals causes significant structural changes, leads to degeneration of crystal quality, and significantly alters superconducting properties. After hydrogenation, a strong correlation was noticed between the structural changes and changes in the parameters characterizing the superconducting state.

【 授权许可】

Unknown