Due to the simple layered structure, isostructural FeSe and FeSe0.5Te0.5 are clue compounds for understanding the principal mechanisms of superconductivity in the family of Fe-based superconductors. High-pressure magnetic, structural and M\"ossbauer studies have been performed on single-crystalline samples of superconducting FeSe0.5Te0.5 with Tc = 13.5 K. Susceptibility data have revealed a strong increase of Tc up to 19.5 K for pressures up to 1.3 GPa, followed by a plateau in the Tc(p) dependence up to 5.0 GPa. Further pressure increase leads to a disappearance of the superconducting state around 7.0 GPa. X-ray diffraction and M\"ossbauer studies explain this fact by a tetragonal-to-hexagonal structural phase transition. M\"ossbauer parameters of the non-superconducting high-pressure phase indicate less covalency of Fe-Se bonds. Based on structural and susceptibility data we conclude about a common character of Tc(p) diagrams for both FeSe and FeSe0.5Te0.5 superconductors.
@article{arxiv.1609.06179,
title = {Pressure effect on superconductivity in FeSe0.5Te0.5},
author = {Sergii I. Shylin and Vadim Ksenofontov and Pavel G. Naumov and Sergey A. Medvedev and Vladimir Tsurkan and Joachim Deisenhofer and Alois Loidl and Leslie M. Schoop and Taras Palasyuk and Gerhard Wortmann and Claudia Felser},
journal= {arXiv preprint arXiv:1609.06179},
year = {2016}
}
Comments
7 pages, 8 figures, published in Phys. Status Solidi B