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arXiv · 2001.03475

Formation and detection of Majorana modes in quantum spin Hall trenches

C. Fleckenstein·N. Traverso Ziani·A. Calzona·M. Sassetti·B. Trauzettel
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Abstract

We propose a novel realization for a topologically superconducting phase hosting Majorana zero-modes on the basis of quantum spin Hall systems. Remarkably, our proposal is completely free of ferromagnets. Instead, we confine helical edge states around a narrow defect line of finite length in a two-dimensional topological insulator. We demonstrate the formation of a new topological regime, hosting protected Majorana modes in the presence of s-wave superconductivity and Zeeman coupling. Interestingly, when the system is weakly tunnel-coupled to helical edge state reservoirs, a particular transport signature is associated with the presence of a non-Abelian Majorana zero-mode.

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C. Fleckenstein, N. Traverso Ziani, A. Calzona, M. Sassetti, B. Trauzettel. 2020-01-10. Formation and detection of Majorana modes in quantum spin Hall trenches. https://doi.org/10.1103/physrevb.103.125303

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