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arXiv · 2207.08430

Conductance of electrostatic wire junctions in bilayer graphene

Sungguen Ryu·Rosa López·Llorenç Serra
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Abstract

The conductance of electrostatic wire junctions in bilayer graphene, classified as trivial-trivial or trivial-topological regarding the confinement character on each junction side, is calculated. The topological side always corresponds to a kink-antikink system, as required for a proper connection with a trivial side. We report a conductance quench of the trivial-topological junction, with a conductance {\it near} quantization to $4e^2/h$, which is only half of the maximum value allowed by the Chern number of a kink-antikink system. The analysis allowed us to uncover the existence of a chiral edge mode in the trivial wire under quite general conditions. A double junction, trivial-topological-trivial, displays periodic Fano-like conductance resonances (dips or peaks) induced by the created topological loop.

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Sungguen Ryu, Rosa López, Llorenç Serra. 2022-07-18. Conductance of electrostatic wire junctions in bilayer graphene. https://doi.org/10.1103/physrevb.106.035424

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