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arXiv · 2307.03779

Chirality probe of twisted bilayer graphene in the linear transport regime

Dario A. Bahamon·Guillermo Gómez-Santos·Dmitri K. Efetov·Tobias Stauber
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Abstract

We propose minimal transport experiments in the coherent regime that can probe the chirality of twisted moir\'e structures. We show that only with a third contact and in the presence of an in-plane magnetic field (or other time-reversal symmetry breaking effect), a chiral system may display non-reciprocal transport in the linear regime. We then propose to use the third lead as a voltage probe and show that opposite enantiomers give rise to different voltage drops on the third lead. Additionally, in the scenario of layer-discriminating contacts, the third lead can serve as a current probe, capable of detecting different handedness even in the absence of a magnetic field. In a complementary configuration, applying opposite voltages on the two layers of the third leads gives rise to a chiral (super)current in the absence of a source-drain voltage whose direction is determined by its chirality.

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Dario A. Bahamon, Guillermo Gómez-Santos, Dmitri K. Efetov, Tobias Stauber. 2023-07-07. Chirality probe of twisted bilayer graphene in the linear transport regime. https://doi.org/10.1021/acs.nanolett.4c00371

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