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Effects of Te- and Fe-doping on the superconducting properties in Fe_ySe_1-_xTe_x thin films.

ABSTRACT: High quality Fe_ySe_1-xTe_x epitaxial thin films have been fabricated on TiO₂-buffered SrTiO₃ substrates by pulsed laser deposition technology. There is a significant composition deviation between the nominal target and the thin film. Te doping can affect the Se/Te ratio and Fe content in chemical composition. The superconducting transition temperature T_c is closely related to the chemical composition. Fe vacancies are beneficial for the Fe_ySe_1-xTe_x films to exhibit the higher T_c. A 3D phase diagram is given that the optimize range is x = 0.13-0.15 and y = 0.73-0.78 for Fe_ySe_1-xTe_x films. The anisotropic, effective pining energy, and critical current density for the Fe_0.72Se_0.94Te_0.06, Fe_0.76Se_0.87Te_0.13 and Fe_0.91Se_0.77Te_0.23 films were studied in detail. The scanning transmission electron microscopy images display a regular atomic arrangement at the interfacial structure.

SUBMITTER: Zhang Y

PROVIDER: S-EPMC8748920 | biostudies-literature |

REPOSITORIES: biostudies-literature

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