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arXiv · 1001.2492

Dynamics of four- versus two-terminal transport through chaotic quantum cavities

M. L. Polianski·M. Buttiker
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Abstract

We consider multi-terminal mesoscopic transport through a well-conducting chaotic quantum cavity using random matrix theory. Four-probe resistance vanishes on the average and is not affected by weak localization. Its fluctuations are given by a single expression valid for arbitrary temperature, ac frequency, non-ideal coupling of the contacts, and in the presence of floating probes; surprisingly, they are governed by the dwell time only. In contrast, the two-probe transport additionally depends on the RC-time, which is interpreted as a property of the measurement scheme. We also predict a universal mesoscopic distribution of the phase of transmitted voltage in an ac experiment.

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M. L. Polianski, M. Buttiker. 2010-01-14. Dynamics of four- versus two-terminal transport through chaotic quantum cavities. https://arxiv.org/abs/1001.2492

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