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Semiclassical theory of a quantum pump

Saar Rahav·Piet W. Brouwer
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Abstract

In a quantum charge pump, the periodic variation of two parameters that affect the phase of the electronic wavefunction causes the flow of a direct current. The operating mechanism of a quantum pump is based on quantum interference, the phases of interfering amplitudes being modulated by the external parameters. In a ballistic quantum dot, there is a minimum time before which quantum interference can not occur: the Ehrenfest time. Here we calculate the current pumped through a ballistic quantum dot when the Ehrenfest time is comparable to the mean dwell time. Remarkably, we find that the pumped current has a component that is not suppressed if the Ehrenfest time is much larger than the mean dwell time.

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Saar Rahav, Piet W. Brouwer. 2006-11-27. Semiclassical theory of a quantum pump. https://doi.org/10.1103/physrevb.74.205327

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