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arXiv · 0905.3286

The quantum Hall effect under the influence of a top-gate and integrating AC lock-in measurements

Tobias Kramer·Eric J. Heller·Robert E. Parrott
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Abstract

Low frequency AC-measurements are commonly used to determine the voltage and currents through mesoscopic devices. We calculate the effect of the alternating Hall voltage on the recorded time-averaged voltage in the presence of a top-gate covering a large part of the device. The gate is kept on a constant voltage, while the Hall voltage is recorded using an integrating alternating-current lock-in technique. The resulting Hall curves show inflection points at the arithmetic mean between two integer plateaus, which are not necessarily related to the distribution of the density of states within a Landau level.

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Tobias Kramer, Eric J. Heller, Robert E. Parrott. 2009-05-20. The quantum Hall effect under the influence of a top-gate and integrating AC lock-in measurements. https://arxiv.org/abs/0905.3286

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