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Quantised charge pumping through multiple quantum dots

Argha Banerjee·Sourin Das·Sumathi Rao
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Abstract

We study electron pumping through a system of barriers, whose heights are deformed adiabatically. We derive a simple formula for the pumped charge $Q$ in terms of the total reflection and transmission amplitudes and phases. The pumped charge increases with the number of barriers ($n_b$) and shows an interesting step-like behaviour, with the steps appearing at integer values of $Q$. The pumped charge also tends towards quantisation with the increase of the amplitude of the time-varying potential. The value of the quantised pumped charge is shown to be correlated to the discontinuity of the reflection phase.

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Argha Banerjee, Sourin Das, Sumathi Rao. 2003-07-14. Quantised charge pumping through multiple quantum dots. https://arxiv.org/abs/cond-mat/0307324

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