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arXiv · 2304.11807

Gate-Defined Topological Josephson Junctions in Bernal Bilayer Graphene

Ying-Ming Xie·Étienne Lantagne-Hurtubise·Andrea F. Young·Stevan Nadj-Perge·Jason Alicea
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Abstract

Recent experiments on Bernal bilayer graphene (BLG) deposited on monolayer WSe$_2$ revealed robust, ultra-clean superconductivity coexisting with sizable induced spin-orbit coupling. Here we propose BLG/WSe$_2$ as a platform to engineer gate-defined planar topological Josephson junctions, where the normal and superconducting regions descend from a common material. More precisely, we show that if superconductivity in BLG/WSe$_2$ is gapped and emerges from a parent state with inter-valley coherence, then Majorana zero modes can form in the barrier region upon applying weak in-plane magnetic fields. Our results spotlight a potential pathway for `internally engineered' topological superconductivity that minimizes detrimental disorder and orbital-magnetic-field effects.

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Ying-Ming Xie, Étienne Lantagne-Hurtubise, Andrea F. Young, Stevan Nadj-Perge, Jason Alicea. 2023-04-24. Gate-Defined Topological Josephson Junctions in Bernal Bilayer Graphene. https://doi.org/10.1103/physrevlett.131.146601

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