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arXiv · 0707.0993

Single-parameter non-adiabatic quantized charge pumping

B. Kaestner·V. Kashcheyevs·S. Amakawa·L. Li·M. D. Blumenthal·T. J. B. M. Janssen·G. Hein·K. Pierz·T. Weimann·U. Siegner·H. W. Schumacher
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Abstract

Controlled charge pumping in an AlGaAs/GaAs gated nanowire by single-parameter modulation is studied experimentally and theoretically. Transfer of integral multiples of the elementary charge per modulation cycle is clearly demonstrated. A simple theoretical model shows that such a quantized current can be generated via loading and unloading of a dynamic quasi-bound state. It demonstrates that non-adiabatic blockade of unwanted tunnel events can obliterate the requirement of having at least two phase-shifted periodic signals to realize quantized pumping. The simple configuration without multiple pumping signals might find wide application in metrological experiments and quantum electronics.

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B. Kaestner, V. Kashcheyevs, S. Amakawa, L. Li, M. D. Blumenthal, T. J. B. M. Janssen, G. Hein, K. Pierz, T. Weimann, U. Siegner, H. W. Schumacher. 2007-07-06. Single-parameter non-adiabatic quantized charge pumping. https://doi.org/10.1103/physrevb.77.153301

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