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Mono-parametric quantum charge pumping: interplay between spatial interference and photon-assisted tunneling

Luis E. F. Foa Torres
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Abstract

We analyze quantum charge pumping in an open ring with a dot embedded in one of its arms. We show that cyclic driving of the dot levels by a \textit{single} parameter leads to a pumped current when a static magnetic flux is simultaneously applied to the ring. Based on the computation of the Floquet-Green's functions, we show that for low driving frequencies $ω_0$, the interplay between the spatial interference through the ring plus photon-assisted tunneling gives an average direct current (dc) which is proportional to $ω_0^{2}$. The direction of the pumped current can be reversed by changing the applied magnetic field.

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Luis E. F. Foa Torres. 2005-11-09. Mono-parametric quantum charge pumping: interplay between spatial interference and photon-assisted tunneling. https://doi.org/10.1103/physrevb.72.245339

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