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arXiv · 1203.3784

Pumping current of a Luttinger liquid with finite length

Sebastián Franchino Viñas·Pablo Pisani·Mariano Salvay
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Abstract

We study transport properties in a Tomonaga-Luttinger liquid in the presence of two time-dependent point like weak impurities, taking into account finite-length effects. By employing analytical methods and performing a perturbation theory, we compute the backscattering pumping current (I_bs) in different regimes which can be established in relation to the oscillatory frequency of the impurities and to the frequency related to the length and the renormalized velocity (by the electron-electron interactions) of the charge density modes. We investigate the role played by the spatial position of the impurity potentials. We also show how the previous infinite length results for I_bs are modified by the finite size of the system.

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Sebastián Franchino Viñas, Pablo Pisani, Mariano Salvay. 2012-03-16. Pumping current of a Luttinger liquid with finite length. https://doi.org/10.1140/epjb/e2012-20928-2

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