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arXiv · 0911.1163

A scattering matrix approach to quantum pumping: Beyond the small-ac-driving-amplitude limit

Rui Zhu
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Abstract

In the adiabatic and weak-modulation quantum pump, net electron flow is driven from one reservoir to the other by absorbing or emitting an energy quantum $\hbar ω$ from or to the reservoirs. In our approach, high-order dependence of the scattering matrix on the time is considered. Non-sinusoidal behavior of strong pumping is revealed. The relation between the pumped current and the ac driving amplitude varies from power of 2, 1 to 1/2 when stronger modulation is exerted. Open experimental observation can be interpreted by multi-energy-quantum-related processes.

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Rui Zhu. 2009-11-06. A scattering matrix approach to quantum pumping: Beyond the small-ac-driving-amplitude limit. https://arxiv.org/abs/0911.1163

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