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تسجيل مستخدم جديدQuantum Correction to Conductivity Close to Ferromagnetic Quantum Critical Point in Two Dimensions
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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/tau gamma (E_{F}tau)^{2}$, where $gamma $ is the parameter associated with the Landau damping of the spin fluctuations, $tau $ 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/tau $. In the ballistic quantum critical regime, the conductivity behaves as $T^{1/3}$.
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