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arXiv · 1312.1630

Selective control of edge-channel trajectories by scanning gate microscopy

N. Paradiso·S. Heun·S. Roddaro·L. N. Pfeiffer·K. W. West·L. Sorba·G. Biasiol·F. Beltram
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Abstract

Electronic Mach-Zehnder interferometers in the Quantum Hall (QH) regime are currently discussed for the realization of quantum information schemes. A recently proposed device architecture employs interference between two co-propagating edge channels. Here we demonstrate the precise control of individual edge-channel trajectories in quantum point contact devices in the QH regime. The biased tip of an atomic force microscope is used as a moveable local gate to pilot individual edge channels. Our results are discussed in light of the implementation of multi-edge interferometers.

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N. Paradiso, S. Heun, S. Roddaro, L. N. Pfeiffer, K. W. West, L. Sorba, G. Biasiol, F. Beltram. 2013-12-05. Selective control of edge-channel trajectories by scanning gate microscopy. https://doi.org/10.1016/j.physe.2009.11.146

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