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arXiv · 1803.11149

Magnetotransport properties in the magnetic phase of BaFe$_{2-x}$T$_x$As$_2$ (T = Co,Ni): A magnetic excitations approach

J. P. Peña·M. M. Piva·P. F. S. Rosa·P. G. Pagliuso·C. Adriano·T. Grant·Z. Fisk·E. Baggio-Saitovitch·P. Pureur
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Abstract

Because of their complex Fermi surfaces, the identification of the physical phenomena contributing to electronic scattering in the Fe-based superconductors is a difficult task. Here, we report on the electrical resistivity, magnetoresistance, and Hall effect in two series of BaFe$_{2-x}$T$_x$As$_2$ (T = Co, Ni) crystals with different values of $x$. The T contents were chosen so that the majority of the investigated samples present an intermediate magnetically ordered state and a superconducting ground state. We interpret the obtained results in terms of scattering of charge carriers by magnetic excitations instead of describing them as resulting uniquely from effects related to multiple-band conduction. Our samples are single crystals from the structural point of view and their overall magnetotransport properties are dominated by a single magnetic state.

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J. P. Peña, M. M. Piva, P. F. S. Rosa, P. G. Pagliuso, C. Adriano, T. Grant, Z. Fisk, E. Baggio-Saitovitch, P. Pureur. 2018-03-29. Magnetotransport properties in the magnetic phase of BaFe$_{2-x}$T$_x$As$_2$ (T = Co,Ni): A magnetic excitations approach. https://doi.org/10.1103/physrevb.97.104502

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