Vortex Structure and Anisotropic Superconducting Gaps in Ba[Fe(Ni)]${}_2$As${}_2$

Abstract

We studied nearly optimally Ni-substituted BaFe${}_{2-x}$Ni${}_x$As${}_2$ (BFNA) single crystals with $T_C\approx 18.5$\,K. In irreversible magnetization measurements, we determined the field dependence of the critical-current density and discuss the nature of observed strong bulk pinning. Using intrinsic multiple Andreev reflections effect (IMARE) spectroscopy, we directly determine two distinct superconducting gaps and resolve their moderate anisotropy in the momentum space. The BCS-ratio for the large gap $2{\Delta }_L/k_B{T}_C>4.1$ evidences for a strong coupling in the ${\Delta }_L$-bands.

arXiv comment6 pages, 4 figures. To be published in Proceedings of Superstripes 2016 Conference

References in corpus (30)

• Superconductivity at 22 K in Co-doped BaFe2As2 Crystals
• Spin density wave anomaly at 140 K in the ternary iron arsenide BaFe2As2
• AC JOSEPHSON EFFECT IN A SINGLE QUANTUM CHANNEL
• Small anisotropy, weak thermal fluctuations, and high field superconductivity in Co-doped iron pnictide Ba(Fe1-xCox)2As2
• Scanning Tunneling Spectroscopy and Vortex Imaging in the Iron-Pnictide Superconductor BaFe${}_{1.8}$Co${}_{0.2}$As${}_2$
• Momentum dependence of the superconducting gap in Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$
• s+is State with Broken Time Reversal Symmetry in Fe-Based Superconductors
• Resonant and crossover phenomena in a multiband superconductor tuning the chemical potential near a band edge
• Quantum Materials: Shape Resonances in Superstripes
• Flux pinning in (1111) iron-pnictide superconducting crystals
• One-sign order parameter in iron based superconductor
• Two-gap superconductivity in Ba_1-xK_xFe_2As_2: A complementary study of the magnetic penetration depth by \muSR and ARPES
• Calorimetric Evidence of Multiband Superconductivity in Ba(Fe0.925Co0.075)2As2
• Behavior of vortices near twin boundaries in underdoped $Ba(F{e}_{1-x}C{o}_x{)}_{2}A{s}_2$
• Feshbach resonances and mesoscopic phase separation near a quantum critical point in multiband FeAs-based superconductors
• Experimental evidence of two-band behavior of MgB2
• Band-edge BCS-BEC crossover in a two-band superconductor: physical properties and detection parameters
• Direct observation of nanoscale interface phase in the superconducting chalcogenide K${}_x$Fe${}_{2-y}$Se${}_2$ with intrinsic phase separation
• First-Principles Study for the Anisotropy of Iron-based Superconductors toward Power and Device Applications
• Nodal gap structure in Fe-based superconductors due to the competition between orbital and spin fluctuations
• Multi-gap superconductivity in single crystals of Ba${}_{0.65}$Na${}_{0.35}$Fe${}_2$As${}_2$: A calorimetric investigation
• Intrinsic arrested nanoscale phase separation near a topological Lifshitz transition in strongly correlated two-band metals
• Strong pinning and vortex energy distributions in single crystalline Ba(Fe1-xCox)2As2
• Lower critical field and SNS-Andreev spectroscopy of 122-arsenides: Evidence of nodeless superconducting gap
• Experimental study of intrinsic multiple Andreev reflections effect in GdO(F)FeAs superconductor array junctions
• Flux jumps and vortex pinning in Ba${}_{0.65}$Na${}_{0.35}$Fe${}_2$As${}_2$ single crystals
• Fish-tail and vortex dynamics in Ni doped iron-pnictide BaFe{1.82}Ni_{0.18}As_2
• Multiple Andreev reflections spectroscopy of two-gap 1111- and 11 Fe-based superconductors
• Evidence for a vortex-glass transition in superconducting Ba(Fe${}_{0.9}$Co${}_{0.1}$)${}_2$As${}_2$
• The flux dynamics behavior of the two competing high temperature superconducting phases in underdoped LaCuO4.06

Cited by in corpus (7)

• On the Structure of Superconducting Order Parameter in High-Temperature Fe-Based Superconductors
• Effect of gap anisotropy on the spin resonance peak in the superconducting state of iron-based materials
• Optical and Hidden Transport Properties of BaFe${}_{1.91}$Ni${}_{0.09}$As${}_2$ Film
• THz electrodynamics of BaFe${}_{1.91}$Ni${}_{0.09}$As${}_2$ film analyzed in the framework of multiband Eliashberg theory
• THz optical response of Ba(Fe${}_{1-x}$Ni${}_x$)${}_2$As${}_2$ films analyzed within the three-band Eliashberg s${}_{\pm }$-wave model
• Lattice, Charge and Spin phase inhomogeneity in complex striped quantum matter
• Optical and transport properties of Ba(Fe${}_{1-x}$Ni${}_x$)${}_2$As${}_2$ films