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arXiv · 0711.4919

Quantum Wire Hybridized with a Single-Level Impurity

Igor V. Lerner·Vladimir I. Yudson·Igor V. Yurkevich
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Abstract

We have studied low-temperature properties of interacting electrons in a one-dimensional quantum wire (Luttinger liquid) side-hybridized with a single-level impurity. The hybridization induces a back-scattering of electrons in the wire which strongly affects its low energy properties. Using a one-loop renormalization group approach valid for a weak electron-electron interaction, we have calculated a transmission coefficient through the wire, $\mathcal{T}(\varepsilon)$, and a local density of states, $ν(\varepsilon)$ at low energies $\varepsilon $. In particular, we have found that the antiresonance in $\mathcal{T}(\varepsilon)$ has a generalized Breit-Wigner shape with the effective width $Γ(\varepsilon)$ which diverges at the Fermi level.

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Igor V. Lerner, Vladimir I. Yudson, Igor V. Yurkevich. 2008-07-10. Quantum Wire Hybridized with a Single-Level Impurity. https://doi.org/10.1103/physrevlett.100.256805

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