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arXiv · 1211.2351

Resonant polaron-assisted tunneling of strongly interacting electrons through a single-level vibrating quantum dot

Gleb A. Skorobagatko
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Abstract

The problem of resonant transport of strongly interacting electrons through a one-dimensional single-level vibrating quantum dot is being considered. In this paper, we generalize the Komnik and Gogolin model [Phys. Rev. Lett., 90, 246403, (2003)] for the single-electron transistor with g=1/2 Luttinger liquid leads to the case of a strong electron-vibron interaction in a quantum dot. The effective transmission coefficient and differential conductance of the system has been derived for the general case of asymmetric tunnel barriers. The main result obtained is that, in the zero-temperature limit, the resonant polaron-assisted tunneling with perfect transmission is possible. This resonant tunneling is of the novel (Andreev-like) type due to a special electron-electron interaction in the leads. As a result, a strong domination of resonant polaron-assisted electron transport at low temperatures has been found. Additional narrowing due to electron-electron interaction in the leads, is roughly the same for all polaron-assisted resonances.

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Gleb A. Skorobagatko. 2012-11-10. Resonant polaron-assisted tunneling of strongly interacting electrons through a single-level vibrating quantum dot. https://doi.org/10.1103/physrevb.85.075310

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