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arXiv · 1812.09957

Resistivity measurements unveil microscopic properties of CrAs

A. Nigro·P. Marra·C. Autieri·W. Wu·J. G. Cheng·J. Luo·C. Noce
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Abstract

We report resistivity measurements of a CrAs single crystal in a wide temperature range, with the specific aim to assess the applicability of the Bloch-Gruneisen formula for electron-phonon resistivity. We find that the resistance reaches a residual value at Tc=4.2 K and its temperature dependence cannot be fitted only with a suitable Bloch-Gruneisen formula in the whole temperature range, even though we are able to calculate a well defined transport Debye temperature. The observed temperature dependent resistivity seems to suggest a non phonon-mediated superconducting pairing, supporting a magnetic fluctuation mechanism as the likely glue for the superconducting coupling.

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A. Nigro, P. Marra, C. Autieri, W. Wu, J. G. Cheng, J. Luo, C. Noce. 2018-12-24. Resistivity measurements unveil microscopic properties of CrAs. https://doi.org/10.1209/0295-5075%2F125%2F57002

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