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Quantum Correction to Conductivity Close to Ferromagnetic Quantum Critical Point in Two Dimensions

I. Paul·C. Pépin·B. N. Narozhny·D. L. Maslov
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Abstract

We study the temperature dependence of the conductivity due to quantum interference processes for a two-dimensional disordered itinerant electron system close to a ferromagnetic quantum critical point. Near the quantum critical point, the cross-over between diffusive and ballistic regimes of quantum interference effects occurs at a temperature $ T^{\ast}=1/τγ(E_{F}τ)^{2}$, where $γ$ is the parameter associated with the Landau damping of the spin fluctuations, $τ$ is the impurity scattering time, and $E_{F}$ is the Fermi energy. For a generic choice of parameters, $T^{\ast}$ is smaller than the nominal crossover scale $1/τ$. In the ballistic quantum critical regime, the conductivity behaves as $T^{1/3}$.

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I. Paul, C. Pépin, B. N. Narozhny, D. L. Maslov. 2006-03-21. Quantum Correction to Conductivity Close to Ferromagnetic Quantum Critical Point in Two Dimensions. https://doi.org/10.1103/physrevlett.95.017206

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