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arXiv · 0809.1670

Coulomb drag in quantum circuits

Alex Levchenko·Alex Kamenev
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Abstract

We study drag effect in a system of two electrically isolated quantum point contacts (QPC), coupled by Coulomb interactions. Drag current exhibits maxima as a function of QPC gate voltages when the latter are tuned to the transitions between quantized conductance plateaus. In the linear regime this behavior is due to enhanced electron-hole asymmetry near an opening of a new conductance channel. In the non-linear regime the drag current is proportional to the shot noise of the driving circuit, suggesting that the Coulomb drag experiments may be a convenient way to measure the quantum shot noise. Remarkably, the transition to the non-linear regime may occur at driving voltages substantially smaller than the temperature.

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Alex Levchenko, Alex Kamenev. 2008-10-22. Coulomb drag in quantum circuits. https://doi.org/10.1103/physrevlett.101.216806

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