Large and significantly anisotropic critical current density induced by planar defects in CaKFe4As4 single crystals

Abstract

Three independent components of critical current density, one for the H//c axis and the other two for the H//ab plane, have been studied in CaKFe4As4 single crystals. When the magnetic field is applied along the c axis, we observed fish-tail-like peaks in the M-H hysteresis loop, and the magnetization at higher temperatures exceeds that at lower temperatures at high fields. When the field is applied parallel to the ab plane, a dip structure is observed in the M-H hysteresis loop near the self-field. In addition, for the H//ab plane, we succeeded in separately evaluating the large and significantly anisotropic in-plane and out-of-plane Jc. Transmission electron microscopy revealed the presence of planar defects parallel to the ab plane in CaKFe4As4, which have not been observed in any other iron-based superconductors. We discuss the possible relationship between the anomalous Jc behavior and the planar defects.

19 pages, 8 figures + supplemental material 6 pages, 4 figures To be published in Phys. Rev. B

References in corpus (9)

• Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
• Nearly Isotropic superconductivity in (Ba,K)Fe2As2
• Vortex phase diagram of Ba(Fe0.93Co0.07)2As2 single crystals
• Fishtail effect and the vortex phase diagram of single crystal Ba0.6K0.4Fe2As2
• Determination of anisotropic Hc2 up to 60 T in (Ba0.55K0.45)Fe2As2 single crystals
• Doping-dependent critical current properties in K, Co, and P-doped BaFe2As2 single crystals
• Magnetic fluctuations and superconducting properties of CaKFe4As4 studied by 75As NMR
• Large, Homogeneous, and Isotropic Critical Current Density in Oxygen-Annealed Fe1+yTe0.6Se0.4 Single Crystal
• Magneto-optical characterizations of FeTe${}_{0.5}$Se${}_{0.5}$ thin films with critical current density over 1 MA/cm${}^2$

Cited by in corpus (6)

• Synthesis of CaKFe${}_4$As${}_4$ bulk samples with high critical current density using a spark plasma sintering technique
• Superconductivity-driven ferromagnetism and spin manipulation using vortices in the magnetic superconductor EuRbFe4As4
• Anomalous second magnetization peak in 12442-type RbCa${}_2$Fe${}_4$As${}_4$F${}_2$ superconductors
• Synthesis of $c$-axis textured CaKFe${}_4$As${}_4$ superconducting bulk via spark plasma texturing technique
• Evolution of Critical Current Density in CaKFe${}_4$As${}_4$ with La-doping
• Superconductivity of Co-Doped CaKFe4As4 Investigated via Point-Contact Spectroscopy and London Penetration Depth Measurements