Increase in Tc and change of crystal structure by high-pressure annealing in BiS2-based superconductor CeO0.3F0.7BiS2

Abstract

Recently, several types of BiS2-based superconductor such as Bi4O4S3, REO1-xFxBiS2 (RE: rare earth) and Sr1-xLaxFBiS2 have been discovered. In this study, we have investigated the crystal structure and the superconducting properties for two kinds of polycrystalline samples (As-grown and high-pressure-annealed samples) of the BiS2-based superconductor CeO0.3F0.7BiS2. We found that both the As-grown and the high-pressure-annealed CeO0.3F0.7BiS2 samples show bulk superconductivity. A higher Tc was observed in the high-pressure-annealed sample. The Tc of CeO0.3F0.7BiS2 increased from Tczero = 2.7 K to Tczero = 3.7 K by high-pressure annealing. The lattice constant of a and c axis did not show remarkable differences between the As-grown and the high-pressure-annealed samples. Nevertheless, the peak symmetry of the (200) peak seemed to become more symmetric while the (004) peak did not show such a difference, indicating that the crystal structure within the ab plane changed to a higher-symmetric phase, a perfect tetragonal, by high-pressure annealing in CeO0.3F0.7BiS2.

13 pages, 3 figures. Submitted to ICSM2014 proceedings

References in corpus (7)

• Superconductivity at 36 K in beta-Fe1.01Se with the compression of the interlayer separation under pressure
• Superconductivity at 27 K in tetragonal FeSe under high pressure
• Superconductivity Appears in the Vicinity of an Insulating-Like Behavior in CeO${}_{1-x}$F${}_x$BiS${}_2$
• Minimal electronic models for superconducting BiS${}_2$ layers
• Superconductivity induced by La doping in Sr1-xLaxFBiS2 system
• Pressure Study of BiS2-Based Superconductors Bi4O4S3 and La(O,F)BiS2
• Evolution of superconductivity in LaO1-xFxBiS2 prepared by high pressure technique

Cited by in corpus (3)

• Effect of hydrostatic pressures on the superconductivity of new BiS2 based REO0.5F0.5BiS2 (RE-La, Pr and Nd) superconductors
• Significant enhancement of superconductivity under hydrostatic pressure in CeO0.5F0.5BiS2 superconductor
• High pressure effects on La(O,F)BiS${}_2$ single crystal using diamond anvil cell with dual-probe diamond electrodes