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arXiv · 1102.4170

Spatially-resolved analysis of edge-channel equilibration in quantum Hall circuits

Nicola Paradiso·Stefan Heun·Stefano Roddaro·Davide Venturelli·Fabio Taddei·Vittorio Giovannetti·Rosario Fazio·Giorgio Biasiol·Lucia Sorba·Fabio Beltram
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Abstract

We demonstrate an innovative quantum Hall circuit with variable geometry employing the moveable electrostatic potential induced by a biased atomic force microscope tip. We exploit this additional degree of freedom to identify the microscopic mechanisms that allow two co-propagating edge channels to equilibrate their charge imbalance. Experimental results are compared with tight-binding simulations based on a realistic model for the disorder potential. This work provides also an experimental realization of a beam mixer between co-propagating edge channels, a still elusive building block of a recently proposed new class of quantum interferometers.

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Nicola Paradiso, Stefan Heun, Stefano Roddaro, Davide Venturelli, Fabio Taddei, Vittorio Giovannetti, Rosario Fazio, Giorgio Biasiol, Lucia Sorba, Fabio Beltram. 2011-02-21. Spatially-resolved analysis of edge-channel equilibration in quantum Hall circuits. https://doi.org/10.1103/physrevb.83.155305

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