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arXiv · 1506.07553

Measuring the Luttinger liquid parameter with shot noise

J. K. Kühne·I. V. Protopopov·Y. Oreg·A. D. Mirlin
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Abstract

We explore the low-frequency noise of interacting electrons in a one-dimensional structure (quantum wire or interaction-coupled edge states) with counterpropagating modes, assuming a single channel in each direction. The system is driven out of equilibrium by a quantum point contact (QPC) with an applied voltage, which induces a double-step energy distribution of incoming electrons on one side of the device. A second QPC serves to explore the statistics of outgoing electrons. We show that measurement of a low-frequency noise in such a setup allows one to extract the Luttinger liquid constant $K$ which is the key parameter characterizing an interacting 1D system. We evaluate the dependence of the zero-frequency noise on $K$ and on parameters of both QPCs (transparencies and voltages).

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J. K. Kühne, I. V. Protopopov, Y. Oreg, A. D. Mirlin. 2015-06-24. Measuring the Luttinger liquid parameter with shot noise. https://doi.org/10.1016/j.physe.2015.08.010

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