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arXiv · 0903.2709

Diagrammatic real-time approach to adiabatic pumping through metallic single-electron devices

Nina Winkler·Michele Governale·Jürgen König
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Abstract

We present a real-time diagrammatic formalism to study adiabatic pumping in chains of tunnel-coupled metallic islands. This approach is based on an expansion to linear order in the frequency of the time-dependent parameters and on a systematic perturbation expansion in the tunnel-coupling strength. We apply our formalism to a single-island and a double-island system. In the single-island setup, we find that the first-order contribution in the tunnel-coupling strength is purely due to the renormalization of the charging-energy gap. In the double-island system, we investigate the transition between weak and strong pumping.

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Nina Winkler, Michele Governale, Jürgen König. 2009-06-05. Diagrammatic real-time approach to adiabatic pumping through metallic single-electron devices. https://doi.org/10.1103/physrevb.79.235309

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