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Separately contacted edge states: A new spectroscopic tool for the investigation of the quantum Hall effect

A. Wuertz·R. Wildfeuer·A. Lorke·E. V. Deviatov·V. T. Dolgopolov
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Abstract

Using an innovative combination of a quasi-Corbino sample geometry and the cross-gate technique, we have developed a method that enables us to separately contact single edge channels in the quantum Hall regime and investigate equilibration among them. Performing 4-point resistance measurements, we directly obtain information on the energetic and geometric structure of the edge region and the equilibration-length for current transport across the Landau- as well as the spin-gap. Based on an almost free choice in the number of participating edge channels and their interaction-length a systematic investigation of the parameter-space becomes possible.

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A. Wuertz, R. Wildfeuer, A. Lorke, E. V. Deviatov, V. T. Dolgopolov. 2001-11-26. Separately contacted edge states: A new spectroscopic tool for the investigation of the quantum Hall effect. https://doi.org/10.1103/physrevb.65.075303

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