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arXiv · 1905.00581

Electron pumping in the strong coupling and non-Markovian regime: A reaction coordinate mapping approach

Sebastian Restrepo·Sina Böhling·Javier Cerrillo·Gernot Schaller
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Abstract

We study electron pumping in the strong coupling and non-Markovian regime. Our model is a single quantum dot with periodically modulated energy and tunnelling amplitudes. We identify four parameters to control the direction of the current: the driving phase, the coupling strength, the driving frequency and the location of the maxima of the spectral density. In the high-frequency regime, we use a Markovian embedding strategy to map our model to three serial quantum dots weakly coupled to the reservoirs allowing us to use a Floquet master equation. We observe a rectification effect of the pumped charge that is exclusive to the non-Markovian character of our model. In the low-frequency regime, we apply an additional transformation to see our model as three independent transport channels. With the use of full counting statistics, we study charge fluctuations and validate that our model behaves as a single electron source.

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Sebastian Restrepo, Sina Böhling, Javier Cerrillo, Gernot Schaller. 2019-08-26. Electron pumping in the strong coupling and non-Markovian regime: A reaction coordinate mapping approach. https://doi.org/10.1103/physrevb.100.035109

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