Critical and Gaussian conductivity fluctuations in BaFe1.9Ni0.1As2 superconductor

Abstract

We study fluctuation conductivity in a single crystal of BaFe${}_{1.9}$Ni${}_{0.1}$As${}_2$ superconductor ($T_c$ = 20 K) as a function of temperature and applied magnetic field. Magneto-conductivity curves, $\Delta \sigma$ vs. $T$, were analyzed in terms of -1/(dln($\Delta \sigma$)/d$T$) vs. $T$ plots, which allow to study different fluctuations regimes and to estimate exponent values and temperature widths of each regime. The analysis of magneto-conductivity curves evidence the existence of only two fluctuations regimes, a possible critical one (of glass-like type) going from the irreversible temperature to above $T_c(H)$ followed by Aslamazov-Larkin fluctuations in the Gaussian regime.

6 pages, 4 figures

References in corpus (8)

• Multiband magnetism and superconductivity in Fe-based compounds
• A review of two-band superconductivity: materials and effects on the thermodynamic and reversible mixed-state properties
• Upper critical field and fluctuation conductivity in the critical regime of doped SmFeAsO
• Multiorbital effects on the transport and the superconducting fluctuations in LiFeAs
• Theory of fluctuation conductivity from interband pairing in pnictide superconductors
• Superconducting fluctuations in the reversible magnetization of the iron-pnictide $B{a}_{1-x}{K}_{x}F{e}_{2}A{s}_2$
• Large $D-2$ Theory of Superconducting Fluctuations in a Magnetic Field and its Application to Iron-Pnictides
• Three-dimensional anisotropic fluctuation diamagnetism around the superconducting transition of Ba(1-x)KxFe2As2 single crystals in the finite-field (or Prange) regime

Cited by in corpus (2)

• Superconducting fluctuations in isovalently-substituted BaFe${}_2$(As${}_{1-x}$P${}_x$)${}_2$: Possible observation of multiband effects
• Fluctuating Cooper pairs in FeSe at temperatures exceeding double Tc