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arXiv · 1311.1336

Non-conventional superconducting fluctuations in Ba(Fe1-xRhx)2As2 iron-based superconductors

L. Bossoni·L. Romanò·P. C. Canfield·A. Lascialfari
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Abstract

We measured the static uniform spin susceptibility of Ba(Fe$_{1-x}$Rh$_x$)$_2$As$_2$ iron-based superconductors, over a broad range of doping ($0.041\leq x\leq 0.094$) and magnetic fields. At small fields ($H \le$ 1 kOe) we observed, above the transition temperature $T_c$, the occurrence of precursor diamagnetism, which is not ascribable to the Ginzburg-Landau theory. On the contrary, our data fit a phase fluctuation model, which has been used to interpret a similar phenomenology occurring in the high-$T_c$ cuprate superconductors. On the other hand, in presence of strong fields the unconventional fluctuating diamagnetism is suppressed, whereas 3D fluctuations are found, in agreement with literature.

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L. Bossoni, L. Romanò, P. C. Canfield, A. Lascialfari. 2014-05-26. Non-conventional superconducting fluctuations in Ba(Fe1-xRhx)2As2 iron-based superconductors. https://doi.org/10.1088/0953-8984%2F26%2F40%2F405703

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