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arXiv · 1007.2062

Constructive role of non-adiabaticity for quantized charge pumping

B. Kaestner·C. Leicht·P. Mirovsky·V. Kashcheyevs·E. V. Kurganova·U. Zeitler·K. Pierz·H. W. Schumacher
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Abstract

We investigate a recently developed scheme for quantized charge pumping based on single-parameter modulation. The device was realized in an AlGaAl-GaAs gated nanowire. It has been shown theoretically that non-adiabaticity is fundamentally required to realize single-parameter pumping, while in previous multi-parameter pumping schemes it caused unwanted and less controllable currents. In this paper we demonstrate experimentally the constructive and destructive role of non-adiabaticity by analysing the pumping current over a broad frequency range.

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B. Kaestner, C. Leicht, P. Mirovsky, V. Kashcheyevs, E. V. Kurganova, U. Zeitler, K. Pierz, H. W. Schumacher. 2010-07-13. Constructive role of non-adiabaticity for quantized charge pumping. https://doi.org/10.1063/1.3666395

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