Coulomb drag in quantum circuits.
نویسندگان
چکیده
We study the drag effect in a system of two electrically isolated quantum point contacts, coupled by Coulomb interactions. Drag current exhibits maxima as a function of quantum point contacts 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 nonlinear 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 nonlinear regime may occur at driving voltages substantially smaller than the temperature.
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ورودعنوان ژورنال:
- Physical review letters
دوره 101 21 شماره
صفحات -
تاریخ انتشار 2008