Evolution of superconducting and transport properties in annealed FeTe${}_{1-x}$Se${}_x$ (0.1 $\le$ $x$ $\le$ 0.4) multiband superconductors

Abstract

We investigated the superconducting and transport properties in FeTe${}_{1-x}$Se${}_x$ (0.1 $\le$ $x$ $\le$ 0.4) single crystals prepared by O${}_2$-annealing. Sharp superconducting transition width observed in magnetization measurement and the small residual resistivity prove the high quality of the crystals. All the crystals manifest large, homogeneous, and isotropic critical current density \emph{J}${}_c$ with self-field value over 10${}^5$ A/cm${}^2$ at 2 K. The large and field-robust critical current densities prove that the superconductivity in FeTe${}_{1-x}$Se${}_x$ (0.1 $\le$ $x$ $\le$ 0.4) is in bulk nature. The values of anisotropy parameter close to $T_c$ for crystals with different Se doping levels all reside in the range of 2 - 3. Hall coefficients $R_H$ keeps positive and almost constant value at high temperatures, followed by a sudden decreases before reaching $T$${}_c$, which indicates that the electron-type charge carriers become dominant at low temperatures. Furthermore, the characteristic temperature for the sudden decrease in $R_H$ gradually increases with Se doping.

12 pages, 7 figures. Invited paper to Supercond. Sci. Technol. (special issue for Multicomponent Superconductivity)

References in corpus (12)

• Density functional study of FeS, FeSe and FeTe: Electronic structure, magnetism, phonons and superconductivity
• Incommensurate magnetic order in the alpha-Fe(Te,Se) superconductor systems
• Bulk Superconductivity at 14 K in Single Crystals of Fe1+yTexSe1-x
• From (pi, 0) magnetic order to superconductivity with (pi, pi) magnetic resonance in Fe1.02(Te1-xSex)
• Fermi surface topology and low-lying quasiparticle dynamics of parent Fe${}_{1+x}$Te/Se Superconductor by orbital-polarization resolved ARPES
• Anisotropy of the Optimally-Doped Iron Pnictide Superconductor Ba(Fe0.926Co0.074)2As2
• Density Functional Study of Excess Fe in Fe${}_{1+x}$Te: Magnetism and Doping
• Dynamics and mechanism of oxygen annealing in Fe${}_{1+y}$Te${}_{0.6}$Se${}_{0.4}$ single crystal
• Multiband Effect and Possible Dirac Fermions in Fe${}_{1+y}$Te${}_{0.6}$Se${}_{0.4}$
• A comprehensive scenario of the single crystal growth and doping dependence of resistivity and anisotropic upper critical fields in (Ba${}_{1-x}$K${}_x$)Fe${}_2$As${}_2$ ($0.22\le x\le 1$)
• Muon-spin-spectroscopy study of the penetration depth of FeTe0.5Se0.5
• Bulk Superconductivity in Fe1+yTe0.6Se0.4 Induced by Removal of Excess Fe

Cited by in corpus (6)

• Non-Thermal Emergence of an Orbital-Selective Mott Phase in FeTe${}_{1-x}$Se${}_x$
• Correlation-Driven Electronic Reconstruction in FeTe${}_{1-x}$Se${}_x$
• Influence of interstitial Fe to the phase diagram of Fe${}_{1+y}$Te${}_{1-x}$Se${}_x$ single crystals
• Incoherent-coherent crossover and the pseudogap in Te-annealed superconducting Fe${}_{1+y}$Te${}_{1-x}$Se${}_x$ revealed by magnetotransport measurements
• Electronic transport properties and hydrostatic pressure effect of FeSe${}_{0.67}$Te${}_{0.33}$ single crystals free of phase separation
• Significant enhancement of critical current density in H+-intercalated FeSe single crystal