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arXiv · 2103.06722

Mechanisms of Andreev reflection in quantum Hall graphene

Antonio L. R. Manesco·Ian Matthias Flór·Chun-Xiao Liu·Anton R. Akhmerov
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Abstract

We simulate a hybrid superconductor-graphene device in the quantum Hall regime to identify the origin of downstream resistance oscillations in a recent experiment [Zhao et. al. Nature Physics 16, (2020)]. In addition to the previously studied Mach-Zehnder interference between the valley-polarized edge states, we consider disorder-induced scattering, and the previously overlooked appearance of the counter-propagating states generated by the interface density mismatch. Comparing our results with the experiment, we conclude that the observed oscillations are induced by the interfacial disorder, and that lattice-matched superconductors are necessary to observe the alternative ballistic effects.

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Antonio L. R. Manesco, Ian Matthias Flór, Chun-Xiao Liu, Anton R. Akhmerov. 2021-03-11. Mechanisms of Andreev reflection in quantum Hall graphene. https://doi.org/10.21468/scipostphyscore.5.3.045

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