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arXiv · 1406.5829

Measurements of the superconducting fluctuations in optimally-doped BaFe$_{2-x}$Ni$_x$As$_2$ under high magnetic fields: Probing the 3D anisotropic Ginzburg-Landau approach

R. I. Rey·A. Ramos-Álvarez·C. Carballeira·J. Mosqueira·F. Vidal·S. Salem-Sugui Jr.·A. D. Alvarenga·Rui Zhang·Huiqian Luo
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Abstract

The superconducting fluctuations well inside the normal state of Fe-based superconductors were experimentally studied through the in-plane paraconductivity in several high-quality optimally-doped BaFe$_{2-x}$Ni$_x$As$_2$ crystals. These measurements were performed in magnetic fields with amplitudes up to 14 T, and different orientations relative to the crystals c axis (0, 53 and 90 degrees). The results allowed a stringent check of the applicability of a recently proposed Ginzburg-Landau approach for the fluctuation electrical conductivity of 3D anisotropic materials in presence of finite applied magnetic fields.

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R. I. Rey, A. Ramos-Álvarez, C. Carballeira, J. Mosqueira, F. Vidal, S. Salem-Sugui Jr., A. D. Alvarenga, Rui Zhang, Huiqian Luo. 2014-06-23. Measurements of the superconducting fluctuations in optimally-doped BaFe$_{2-x}$Ni$_x$As$_2$ under high magnetic fields: Probing the 3D anisotropic Ginzburg-Landau approach. https://doi.org/10.1088/0953-2048%2F27%2F7%2F075001

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