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arXiv · 1401.1960

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

S. Salem-Sugui, Jr.·A. D. Alvarenga·R. I. Rey·J. Mosqueira·H-Q Luo·X-Y Lu
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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, $Δσ$ vs. $T$, were analyzed in terms of -1/(dln($Δσ$)/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.

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S. Salem-Sugui, Jr., A. D. Alvarenga, R. I. Rey, J. Mosqueira, H-Q Luo, X-Y Lu. 2014-01-09. Critical and Gaussian conductivity fluctuations in BaFe1.9Ni0.1As2 superconductor. https://doi.org/10.1088/0953-2048%2F26%2F12%2F125019

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