Pressure effect on superconductivity in FeSe0.5Te0.5

Abstract

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 Mössbauer 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 Mössbauer studies explain this fact by a tetragonal-to-hexagonal structural phase transition. Mössbauer 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.

7 pages, 8 figures, published in Phys. Status Solidi B

References in corpus (8)

• Superconductivity at 36 K in beta-Fe1.01Se with the compression of the interlayer separation under pressure
• Superconductivity close to magnetic instability in Fe(Se1-xTex)0.82
• The Structural Phase Transition in FeSe (Fe1+dSe)
• Bulk Superconductivity at 14 K in Single Crystals of Fe1+yTexSe1-x
• Why Does Undoped FeSe Become A High Tc Superconductor Under Pressure?
• Orbital-driven nematicity in FeSe
• Electronic Structure and Superconductivity of FeSe-Related Superconductors
• Physical properties of FeSe${}_{0.5}$Te${}_{0.5}$ single crystals grown under different conditions