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arXiv · 0710.5011

A precursor state to unconventional superconductivity in CeIrIn${_5}$

Sunil Nair·S. Wirth·M. Nicklas·J. L. Sarrao·J. D. Thompson·Z. Fisk·F. Steglich
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Abstract

We present sensitive measurements of the Hall effect and magnetoresistance in CeIrIn${_5}$ down to temperatures of 50 mK and magnetic fields up to 15 T. The presence of a low temperature coherent Kondo state is established. Deviations from Kohler's rule and a quadratic temperature dependence of the cotangent of the Hall angle are reminiscent of properties observed in the high temperature superconducting cuprates. The most striking observation pertains to the presence of a \textit{precursor} state--characterized by a change in the Hall mobility--that appears to precede the superconductivity in this material, in similarity to the pseudogap in the cuprate high $T_c$ superconductors.

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Sunil Nair, S. Wirth, M. Nicklas, J. L. Sarrao, J. D. Thompson, Z. Fisk, F. Steglich. 2007-10-26. A precursor state to unconventional superconductivity in CeIrIn${_5}$. https://doi.org/10.1103/physrevlett.100.137003

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