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Polarized Magnetic Wire Induced by Tunneling Through a Magnetic Impurity

D. Schmeltzer·A. R. Bishop·A. Saxena·D. Smith
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Abstract

Using the zero mode method we compute the conductance of a wire consisting of a magnetic impurity coupled to two Luttinger liquid leads characterized by the Luttinger exponent $α(\leq 1)$. We find for resonance conditions, in which the Fermi energy of the leads is close to a single particle energy of the impurity, the conductance as a function of temperature is $G \sim \frac{e^2}{h} (T/T_F)^{2(α-2)}$, whereas for off-resonance conditions the conductance is $G \sim \frac{e^2}{h} (T/T_F)^{2(α-1)}$. By applying a gate voltage and/or a magnetic field, one of the spin components can be in resonance while the other is off-resonance causing a strong asymmetry between the spin-up and spin-down conductances.

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D. Schmeltzer, A. R. Bishop, A. Saxena, D. Smith. 2002-11-20. Polarized Magnetic Wire Induced by Tunneling Through a Magnetic Impurity. https://doi.org/10.1103/physrevlett.90.116802

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