Anisotropic superconducting properties of single-crystallineFeSe0.5Te0.5

2010/04/06 by M. Bendele, S. Weyeneth, R. Puźniak +12 · 2 citations
Business, Management and Accounting · Chemistry · Materials Science · Physics and Astronomy · #Chemistry #Condensed matter physics #Corporate Taxation and Avoidance #Crystal structure #Crystallography #Iron-based superconductors research #Lambda #London penetration depth #Neutron diffraction #Phase (matter) #Physics #Quantum mechanics #Superconductivity #Tetragonal crystal system #cond-mat.supr-con

paper · pdf · doi:10.1103/physrevb.81.224520

published as Phys. Rev. B 81, 224520 (2010)

arxiv created 2010/04/06 · openalex publication_date 2010/06/28 · arxiv updated 2015/03/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

Iron-chalcogenide single crystals with the nominal composition FeSe_0.5Te_0.5 and a transition temperature of T_c\ensuremath≃14.6 K were synthesized by the Bridgman method. The structural and anisotropic superconducting properties of those crystals were investigated by means of single crystal x-ray and neutron powder diffraction, superconducting quantum interference device and torque magnetometry, and muon-spin rotation (\ensuremathμSR). Room temperature neutron powder diffraction reveals that 95% of the crystal volume is of the same tetragonal structure as PbO. The structure refinement yields a stoichiometry of Fe_1.045Se_0.406Te_0.594. Additionally, a minor hexagonal Fe₇Se₈ impurity phase was identified. The magnetic penetration depth \ensuremathλ at zero temperature obtained by means of \ensuremathμSR was found to be \ensuremathλ_ab(0)=491(8) nm in the ab plane and \ensuremathλ_c(0)=1320(14) nm along the c axis. The zero-temperature value of the superfluid density \ensuremathρ_s(0)\ensuremath∝\ensuremathλ^\ensuremath-2(0) obeys the empirical Uemura relation observed for various unconventional superconductors, including cuprates and iron pnictides. The temperature dependences of both \ensuremathλ_ab and \ensuremathλ_c are well described by a two-gap s+s-wave model with the zero-temperature gap values of \ensuremathΔ_S(0)=0.51(3) meV and \ensuremathΔ_L(0)=2.61(9) meV for the small and the large gap, respectively. The magnetic penetration depth anisotropy parameter \ensuremathγ_\ensuremathλ(T)=\ensuremathλ_c(T)/\ensuremathλ_ab(T) increases with decreasing temperature, in agreement with \ensuremathγ_\ensuremathλ(T) observed in the iron-pnictide superconductors.

Citations

• Superfluid density and penetration depth in the iron pnictides
• First-order magnetic and structural phase transitions inFe1+ySexTe1−x
• Recent advances in magnetic structure determination by neutron powder diffraction
• The superconductivity at 18 K in LiFeAs system
• The electronic phase diagram of the LaO1−xFxFeAs superconductor
• Anisotropy of Superconducting Single Crystal SmFeAsO0.8F0.2 Studied by Torque Magnetometry
• Two-band superconductivity in LaFeAsO0.89F0.11 at very high magnetic fields
• Superconductivity at 27K in tetragonal FeSe under high pressure
• Superconductivity at 52 K in iron based F doped layered quaternary compound Pr[O1–xFx]FeAs
• Superconductivity at 17 K in (Fe2P2)(Sr4Sc2O6): a new superconducting layered pnictide oxide with a thick perovskite oxide layer
• Multiple Gap Symmetries for the Order Parameter of Cuprate Superconductors from Penetration Depth Measurements
• Probing the Superconducting Energy Gap from Infrared Spectroscopy on aBa0.6K0.4Fe2As2Single Crystal withTc=37 K
• Superconductivity in the iron-based F-doped layered quaternary compound Nd[O 1 − x F x ]FeAs
• Muon-spin-spectroscopy study of the penetration depth ofFeTe0.5Se0.5
• Superconductivity at 38 K in the Iron Arsenide(Ba1−xKx)Fe2As2

Cited by

• Calorimetric evidence of strong-coupling multiband superconductivity in Fe(Te0.57Se0.43) single crystal
• Self-Consistent Two-Gap Approach in Studying Multi-Band Superconductivity of NdFeAsO0.65F0.35
• Bolometric Superconducting Optical Nanoscopy (BOSON)