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Interplay of disorder and spin fluctuations in the resistivity near a quantum critical point

A. Rosch
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Abstract

The resistivity in metals near an antiferromagnetic quantum critical point (QCP) is strongly affected by small amounts of disorder. In a quasi-classical treatment, we show that an interplay of strongly anisotropic scattering due to spin fluctuations and isotropic impurity scattering leads to a large regime where the resistivity varies as T^alpha, with an anomalous exponent, alpha, 1 <= alpha <= 1.5, depending on the amount of disorder. I argue that this mechanism explains in some detail the anomalous temperature dependence of the resistivity observed in CePd_2Si_2, CeNi_2Ge_2 and CeIn_3 near the QCP.

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A. Rosch. 1999-05-14. Interplay of disorder and spin fluctuations in the resistivity near a quantum critical point. https://doi.org/10.1103/physrevlett.82.4280

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