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arXiv · 2209.11080

Chiral Majorana Modes via Proximity to a Twisted Cuprate Bilayer

Gilad Margalit·Binghai Yan·Marcel Franz·Yuval Oreg
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Abstract

We propose a novel heterostructure to achieve chiral topological superconductivity in 2D. A substrate with a large Rashba spin-orbit coupling energy is brought in proximity to a twisted bilayer of thin films exfoliated from a high-temperature cuprate superconductor. The combined system is then exposed to an out-of-plane magnetic field. The rare $d + id$ pairing symmetry expected to occur in such a system allows for nontrivial topology; specifically, in contrast to the case of the twisted bilayer in isolation, the substrate induces an odd Chern number. The resulting phase is characterized by the presence of a Majorana zero mode in each vortex.

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Gilad Margalit, Binghai Yan, Marcel Franz, Yuval Oreg. 2022-09-22. Chiral Majorana Modes via Proximity to a Twisted Cuprate Bilayer. https://doi.org/10.1103/physrevb.106.205424

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