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arXiv · 2504.12049

Impact of spin correlations on resistivity and microwave absorption of Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$

Yu. I. Talanov·I. I. Gimazov·D. E. Zhelezniakova
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Abstract

The results of studies of BaFe$_2$As$_2$ single crystals doped with cobalt by means of resistivity and microwave absorption measurement are reported. A theoretical description of the behavior of the microwave absorption amplitude is made taking into account the temperature dependence of resistivity, magnetic susceptibility and the lifetime of spin fluctuations. An assumption has been made that the deviation from the linear dependence of resistivity on temperature at $T<100$ K is not related to the electron-electron scattering mechanism, but it is due to the appearance of nematic fluctuations. Estimates of the rate of scattering by spin fluctuations indicate their nematic nature at temperatures near the structural transition.

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Yu. I. Talanov, I. I. Gimazov, D. E. Zhelezniakova. 2025-04-16. Impact of spin correlations on resistivity and microwave absorption of Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$. https://doi.org/10.26907/mrsej-24110

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